How to parse optional fields from left to right with BizTalk flat file parser set to complex?

I am developing a schema for flat file disassembly in BizTalk 2013. However, I have a big problem with the schema, since the parsing result is rubbish. The flat file type I am parsing looks like this:

HEADER:opt1:opt2:opt3+opt4:opt5+opt6+op7:opt8:opt9'
TAG1:opt1:opt2:opt3+opt4:opt5:opt6+op7:opt8:opt9'
TAG2:opt1:opt2:opt3+opt4:opt5:opt6+op7:opt8:opt9'
TAG3:opt1:opt2:opt3+opt4++opt6+op7:opt8:opt9'
TAG4:opt1:opt2:opt3+opt4:opt5'

The flat file has three hierarchy parts:

Top level: Segments, delimited by ' characters (not the line break, this was just added for better readability)

Middle level: Fields, delimited by + characters. May directly contain a value or a group of values (see bottom level)

Bottom level: Attributes, delimited by : characters

Since the TAG?-Segments are partially optional and may occur in multiple orders, I am using the parser_optimization="complexity" option along with lookahead_depth="0" and use the TAG?-Name to identify the segment types, I am using to parse everything. All delimiters are of child_order="infix" except the segments, which are child_order="postfix".

Some Segments, fields and attributes are required, most are not. However, the first field and its attributes (tag name, ...) is always required. The separation and identification of segments works fine, fields also are working correctly. However, when I am having optional fields containing a group of optional attributes, the schema does not get parsed correctly. Example: Syntax:

TAGX:opt1:opt2:opt3+a1:a2:a3:a4:a5:a6'

All a? attributes are optional

The attribute values are being put into the correct XML fields while parsing a segment like this:

TAGX:1:2:3+:1:2:::'

However, since the flat file specification allows optional fields to be left out, the message may also look like this:

TAGX:1:2:3+:1:2'

In this case, the values are not being put into the second and third XML field like they should be but are put into the third and fourth. Depending on the amount of : signs I include into the segment, also the first and sixth or second and fourth XML field may be filled.

I would need the flat file parser to fill these fields form the left to the right instead of the chaotic way it is using now. However, switching to parser_optimization="speed" is not an option since the rest of the schema is too complex (unless, there is a way to do that locally).

These are the parts of the XSD schema that are being used for parsing such a field (only the extracted parts, since the schema is very big)

Common parts definition (gets included in the schema itself, is being used by other schemas as well, in this example it is a 4 part Attribute group):

<?xml version="1.0" encoding="utf-16"?>
<xs:schema xmlns:b="http://schemas.microsoft.com/BizTalk/2003" xmlns:xs="http://www.w3.org/2001/XMLSchema" elementFormDefault="qualified" attributeFormDefault="unqualified">
    <xs:annotation>
        <xs:appinfo>
            <schemaEditorExtension:schemaInfo namespaceAlias="b" extensionClass="Microsoft.BizTalk.FlatFileExtension.FlatFileExtension" standardName="Flat File" xmlns:schemaEditorExtension="http://schemas.microsoft.com/BizTalk/2003/SchemaEditorExtensions"/>
            <b:schemaInfo root_reference="SEG_HEAD" pad_char_type="none" count_positions_by_byte="false" parser_optimization="speed" lookahead_depth="3" suppress_empty_nodes="false" generate_empty_nodes="true" allow_early_termination="false" early_terminate_optional_fields="false" allow_message_breakup_of_infix_root="false" compile_parse_tables="false" standard="Flat File" default_pad_char=" "/>
        </xs:appinfo>
    </xs:annotation>

    <xs:element name="MATERIAL_TYPE" type="MATERIAL_TYPE">
        <xs:annotation>
            <xs:appinfo>
                <b:recordInfo sequence_number="4" structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" child_delimiter_type="char" child_delimiter=":" escape_char_type="char" escape_char="?" child_order="infix"/>
            </xs:appinfo>
        </xs:annotation>
    </xs:element>
    <xs:complexType name="MATERIAL_TYPE">
        <xs:sequence>
            <xs:annotation>
                <xs:appinfo>
                    <b:groupInfo sequence_number="0"/>
                </xs:appinfo>
            </xs:annotation>
            <xs:element name="NUMBER_SYSTEM" type="xs:string" minOccurs="0">
                <xs:annotation>
                    <xs:appinfo>
                        <b:fieldInfo sequence_number="1" justification="left"/>
                    </xs:appinfo>
                </xs:annotation>
            </xs:element>
            <xs:element name="MATERIAL" type="xs:string" minOccurs="0">
                <xs:annotation>
                    <xs:appinfo>
                        <b:fieldInfo sequence_number="2" justification="left"/>
                    </xs:appinfo>
                </xs:annotation>
            </xs:element>
            <xs:element name="EAN" type="xs:string" minOccurs="0">
                <xs:annotation>
                    <xs:appinfo>
                        <b:fieldInfo sequence_number="3" justification="left"/>
                    </xs:appinfo>
                </xs:annotation>
            </xs:element>
            <xs:element name="BUYERARTICLENUMBER" type="xs:string" minOccurs="0">
                <xs:annotation>
                    <xs:appinfo>
                        <b:fieldInfo sequence_number="4" justification="left"/>
                    </xs:appinfo>
                </xs:annotation>
            </xs:element>
        </xs:sequence>
    </xs:complexType>
</xs:schema>

Specific schema extract:

<?xml version="1.0" encoding="utf-16"?>
<xs:schema xmlns="http://example.com/namespace" xmlns:b="http://schemas.microsoft.com/BizTalk/2003" xmlns:xs="http://www.w3.org/2001/XMLSchema" targetNamespace="http://example.com/namespace" elementFormDefault="qualified" attributeFormDefault="unqualified">
    <xs:include schemaLocation=".\COMMON_SChema_v2.0.xsd"/>
    <xs:annotation>
        <xs:appinfo>
            <b:schemaInfo standard="Flat File" root_reference="SEG_ORDER" pad_char_type="none" count_positions_by_byte="false" parser_optimization="complexity" lookahead_depth="0" suppress_empty_nodes="true" generate_empty_nodes="true" allow_early_termination="false" early_terminate_optional_fields="false" allow_message_breakup_of_infix_root="false" compile_parse_tables="false" default_pad_char=" " escape_char_type="char" default_escape_char="?" default_child_order="infix"/>
            <schemaEditorExtension:schemaInfo namespaceAlias="b" extensionClass="Microsoft.BizTalk.FlatFileExtension.FlatFileExtension" standardName="Flat File" xmlns:schemaEditorExtension="http://schemas.microsoft.com/BizTalk/2003/SchemaEditorExtensions"/>
        </xs:appinfo>
    </xs:annotation>
    <xs:element name="SEG_ORDER">
        <xs:annotation>
            <xs:appinfo>
                <b:recordInfo structure="delimited" child_order="postfix" escape_char_type="char" escape_char="?" sequence_number="17" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" child_delimiter_type="char" child_delimiter="'"/>
            </xs:appinfo>
        </xs:annotation>
        <xs:complexType>
            <xs:sequence>
                <xs:annotation>
                    <xs:appinfo>
                        <b:groupInfo sequence_number="0"/>
                    </xs:appinfo>
                </xs:annotation>

                <xs:element name="TAGX" maxOccurs="unbounded">
                    <xs:annotation>
                        <xs:appinfo>
                            <b:recordInfo structure="delimited" child_delimiter_type="char" child_delimiter="+" child_order="infix" escape_char_type="char" escape_char="?" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" sequence_number="6" tag_name="TAGX"/>
                        </xs:appinfo>
                    </xs:annotation>
                    <xs:complexType>
                        <xs:sequence>
                            <xs:annotation>
                                <xs:appinfo>
                                    <b:groupInfo sequence_number="0"/>
                                </xs:appinfo>
                            </xs:annotation>
                            <xs:element name="SEG_HEAD" type="SEG_HEAD_REF1_TYPE">
                                <xs:annotation>
                                    <xs:appinfo>
                                        <b:recordInfo structure="delimited" child_delimiter_type="char" child_delimiter=":" escape_char_type="char" escape_char="?" sequence_number="1" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" child_order="prefix"/>
                                    </xs:appinfo>
                                </xs:annotation>
                            </xs:element>
                            <xs:element name="POSITION_NUMBER">
                                <xs:annotation>
                                    <xs:appinfo>
                                        <b:recordInfo structure="delimited" child_delimiter_type="char" child_delimiter=":" child_order="infix" escape_char_type="char" escape_char="?" sequence_number="2" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false"/>
                                    </xs:appinfo>
                                </xs:annotation>
                                <xs:complexType>
                                    <xs:sequence>
                                        <xs:annotation>
                                            <xs:appinfo>
                                                <b:groupInfo sequence_number="0"/>
                                            </xs:appinfo>
                                        </xs:annotation>
                                        <xs:element name="NUMBER" type="xs:string">
                                            <xs:annotation>
                                                <xs:appinfo>
                                                    <b:fieldInfo justification="left" sequence_number="1"/>
                                                </xs:appinfo>
                                            </xs:annotation>
                                        </xs:element>
                                    </xs:sequence>
                                </xs:complexType>
                            </xs:element>
                            <xs:element name="MATERIAL" type="MATERIAL_TYPE" minOccurs="0" maxOccurs="1">
                                <xs:annotation>
                                    <xs:appinfo>
                                        <b:recordInfo structure="delimited" child_delimiter_type="char" child_delimiter=":" child_order="infix" escape_char_type="char" escape_char="?" sequence_number="3" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false"/>
                                    </xs:appinfo>
                                </xs:annotation>
                            </xs:element>
                        </xs:sequence>
                    </xs:complexType>
                </xs:element>
            </xs:sequence>
        </xs:complexType>
    </xs:element>
</xs:schema>

Your Specific Extract is missing a definition for SEG_HEAD_REF1_TYPE and there were other issues as well that when I tried to generate an instance I got "Custom component invocation failed." However I created a flat file schema based on your flat file mock sample that parses that as well as the sample below correctly. (Note: I had to remove indenting from the schema otherwise it would be too large to post).

<?xml version="1.0" encoding="utf-16"?>
<xs:schema xmlns="http://Scratch.FlatFileSchema2" xmlns:b="http://schemas.microsoft.com/BizTalk/2003" targetNamespace="http://Scratch.FlatFileSchema2" xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:annotation>
<xs:appinfo>
<b:schemaInfo standard="Flat File" root_reference="Root" default_pad_char=" " pad_char_type="char" count_positions_by_byte="false" parser_optimization="speed" lookahead_depth="3" suppress_empty_nodes="false" generate_empty_nodes="true" allow_early_termination="false" early_terminate_optional_fields="false" allow_message_breakup_of_infix_root="false" compile_parse_tables="false" />
<schemaEditorExtension:schemaInfo namespaceAlias="b" extensionClass="Microsoft.BizTalk.FlatFileExtension.FlatFileExtension" standardName="Flat File" xmlns:schemaEditorExtension="http://schemas.microsoft.com/BizTalk/2003/SchemaEditorExtensions" />
</xs:appinfo>
</xs:annotation>
<xs:element name="Root">
<xs:annotation>
<xs:appinfo>
<b:recordInfo structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" sequence_number="1" child_order="postfix" child_delimiter_type="char" child_delimiter="'" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element name="Header">
<xs:annotation>
<xs:appinfo>
<b:recordInfo sequence_number="1" structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" tag_name="HEADER" child_order="infix" child_delimiter_type="char" child_delimiter="+" escape_char_type="char" escape_char="?" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element name="Field1">
<xs:annotation>
<xs:appinfo>
<b:recordInfo sequence_number="1" structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" child_order="prefix" child_delimiter_type="char" child_delimiter=":" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element name="Attr1" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="1" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr2" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="2" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr3" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element minOccurs="0" name="Field2">
<xs:annotation>
<xs:appinfo>
<b:recordInfo structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" child_order="infix" child_delimiter_type="char" child_delimiter=":" sequence_number="2" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element minOccurs="0" name="Attr1" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="1" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr2" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="2" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr3" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element minOccurs="0" name="Field3">
<xs:annotation>
<xs:appinfo>
<b:recordInfo structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" child_order="infix" child_delimiter_type="char" child_delimiter=":" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element minOccurs="0" name="Attr1" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="1" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr2" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="2" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr3" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element minOccurs="0" name="Field4">
<xs:annotation>
<xs:appinfo>
<b:recordInfo structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" child_order="infix" child_delimiter_type="char" child_delimiter=":" sequence_number="4" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element minOccurs="0" name="Attr1" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="1" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr2" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="2" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr3" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="TAG1">
<xs:annotation>
<xs:appinfo>
<b:recordInfo sequence_number="2" structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" tag_name="TAG1" child_order="infix" child_delimiter_type="char" child_delimiter="+" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element name="Field1">
<xs:annotation>
<xs:appinfo>
<b:recordInfo structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" child_order="prefix" child_delimiter_type="char" child_delimiter=":" sequence_number="1" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element name="Attr1" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="1" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr2" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="2" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr3" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element minOccurs="0" name="Field2">
<xs:annotation>
<xs:appinfo>
<b:recordInfo structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" child_order="infix" child_delimiter_type="char" child_delimiter=":" sequence_number="2" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element minOccurs="0" name="Attr1" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="1" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr2" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="2" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr3" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element minOccurs="0" name="Field3">
<xs:annotation>
<xs:appinfo>
<b:recordInfo structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" child_order="infix" child_delimiter_type="char" child_delimiter=":" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element minOccurs="0" name="Attr1" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="1" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr2" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="2" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr3" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element minOccurs="0" name="Field4">
<xs:annotation>
<xs:appinfo>
<b:recordInfo structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" child_order="infix" child_delimiter_type="char" child_delimiter=":" sequence_number="4" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element minOccurs="0" name="Attr1" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="1" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr2" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="2" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr3" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="TAG2">
<xs:annotation>
<xs:appinfo>
<b:recordInfo structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" tag_name="TAG2" child_order="infix" child_delimiter_type="char" child_delimiter="+" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element name="Field1">
<xs:annotation>
<xs:appinfo>
<b:recordInfo structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" child_order="prefix" child_delimiter_type="char" child_delimiter=":" sequence_number="1" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element name="Attr1" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="1" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr2" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="2" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr3" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element minOccurs="0" name="Field2">
<xs:annotation>
<xs:appinfo>
<b:recordInfo structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" child_order="infix" child_delimiter_type="char" child_delimiter=":" sequence_number="2" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element minOccurs="0" name="Attr1" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="1" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr2" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="2" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr3" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element minOccurs="0" name="Field3">
<xs:annotation>
<xs:appinfo>
<b:recordInfo structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" child_order="infix" child_delimiter_type="char" child_delimiter=":" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element minOccurs="0" name="Attr1" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="1" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr2" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="2" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr3" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element minOccurs="0" name="Field4">
<xs:annotation>
<xs:appinfo>
<b:recordInfo structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" child_order="infix" child_delimiter_type="char" child_delimiter=":" sequence_number="4" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element minOccurs="0" name="Attr1" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="1" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr2" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="2" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr3" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="TAG3">
<xs:annotation>
<xs:appinfo>
<b:recordInfo structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" tag_name="TAG3" child_order="infix" child_delimiter_type="char" child_delimiter="+" sequence_number="4" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element name="Field1">
<xs:annotation>
<xs:appinfo>
<b:recordInfo structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" child_order="prefix" child_delimiter_type="char" child_delimiter=":" sequence_number="1" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element name="Attr1" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="1" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr2" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="2" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr3" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element minOccurs="0" name="Field2">
<xs:annotation>
<xs:appinfo>
<b:recordInfo structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" child_order="infix" child_delimiter_type="char" child_delimiter=":" sequence_number="2" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element minOccurs="0" name="Attr1" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="1" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr2" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="2" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr3" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element minOccurs="0" name="Field3">
<xs:annotation>
<xs:appinfo>
<b:recordInfo structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" child_order="infix" child_delimiter_type="char" child_delimiter=":" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element minOccurs="0" name="Attr1" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="1" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr2" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="2" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr3" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element minOccurs="0" name="Field4">
<xs:annotation>
<xs:appinfo>
<b:recordInfo structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" child_order="infix" child_delimiter_type="char" child_delimiter=":" sequence_number="4" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element minOccurs="0" name="Attr1" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="1" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr2" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="2" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr3" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="TAG4">
<xs:annotation>
<xs:appinfo>
<b:recordInfo structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" tag_name="TAG4" child_order="infix" child_delimiter_type="char" child_delimiter="+" sequence_number="5" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element name="Field1">
<xs:annotation>
<xs:appinfo>
<b:recordInfo structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" child_order="prefix" child_delimiter_type="char" child_delimiter=":" sequence_number="1" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element name="Attr1" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="1" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr2" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="2" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr3" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element minOccurs="0" name="Field2">
<xs:annotation>
<xs:appinfo>
<b:recordInfo structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" child_order="infix" child_delimiter_type="char" child_delimiter=":" sequence_number="2" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element minOccurs="0" name="Attr1" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="1" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr2" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="2" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr3" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element minOccurs="0" name="Field3">
<xs:annotation>
<xs:appinfo>
<b:recordInfo structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" child_order="infix" child_delimiter_type="char" child_delimiter=":" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element minOccurs="0" name="Attr1" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="1" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr2" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="2" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr3" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element minOccurs="0" name="Field4">
<xs:annotation>
<xs:appinfo>
<b:recordInfo structure="delimited" preserve_delimiter_for_empty_data="true" suppress_trailing_delimiters="false" child_order="infix" child_delimiter_type="char" child_delimiter=":" sequence_number="4" />
</xs:appinfo>
</xs:annotation>
<xs:complexType>
<xs:sequence>
<xs:annotation>
<xs:appinfo>
<b:groupInfo sequence_number="0" />
</xs:appinfo>
</xs:annotation>
<xs:element minOccurs="0" name="Attr1" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="1" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr2" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="2" />
</xs:appinfo>
</xs:annotation>
</xs:element>
<xs:element minOccurs="0" name="Attr3" type="xs:string">
<xs:annotation>
<xs:appinfo>
  <b:fieldInfo justification="left" sequence_number="3" />
</xs:appinfo>
</xs:annotation>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:schema>

Sample

HEADER:opt1'TAG1:opt1'TAG2:opt1'TAG3:opt1'TAG4:opt1'

来源：https://stackoverflow.com/questions/21990744/how-to-parse-optional-fields-from-left-to-right-with-biztalk-flat-file-parser-se

标签

xml

parsing

xsd

biztalk

biztalk-2013