问题
I'm looking for a class that can output an object and all its leaf values in a format similar to this:
User
- Name: Gordon
- Age : 60
- WorkAddress
- Street: 10 Downing Street
- Town: London
- Country: UK
- HomeAddresses[0]
...
- HomeAddresses[1]
...
(Or a clearer format). This would be equivalent to:
public class User
{
public string Name { get;set; }
public int Age { get;set; }
public Address WorkAddress { get;set; }
public List<Address> HomeAddresses { get;set; }
}
public class Address
{
public string Street { get;set; }
public string Town { get;set; }
public string Country { get;set; }
}
A kind of string representation of the PropertyGrid control, minus having to implement a large set of designers for each type.
PHP has something that does this called var_dump. I don't want to use a watch, as this is for printing out.
Could anyone point me to something like this if it exists? Or, write one for a bounty.
回答1:
The object dumper posted in sgmoore's link:
//Copyright (C) Microsoft Corporation. All rights reserved.
using System;
using System.IO;
using System.Collections;
using System.Collections.Generic;
using System.Reflection;
// See the ReadMe.html for additional information
public class ObjectDumper {
public static void Write(object element)
{
Write(element, 0);
}
public static void Write(object element, int depth)
{
Write(element, depth, Console.Out);
}
public static void Write(object element, int depth, TextWriter log)
{
ObjectDumper dumper = new ObjectDumper(depth);
dumper.writer = log;
dumper.WriteObject(null, element);
}
TextWriter writer;
int pos;
int level;
int depth;
private ObjectDumper(int depth)
{
this.depth = depth;
}
private void Write(string s)
{
if (s != null) {
writer.Write(s);
pos += s.Length;
}
}
private void WriteIndent()
{
for (int i = 0; i < level; i++) writer.Write(" ");
}
private void WriteLine()
{
writer.WriteLine();
pos = 0;
}
private void WriteTab()
{
Write(" ");
while (pos % 8 != 0) Write(" ");
}
private void WriteObject(string prefix, object element)
{
if (element == null || element is ValueType || element is string) {
WriteIndent();
Write(prefix);
WriteValue(element);
WriteLine();
}
else {
IEnumerable enumerableElement = element as IEnumerable;
if (enumerableElement != null) {
foreach (object item in enumerableElement) {
if (item is IEnumerable && !(item is string)) {
WriteIndent();
Write(prefix);
Write("...");
WriteLine();
if (level < depth) {
level++;
WriteObject(prefix, item);
level--;
}
}
else {
WriteObject(prefix, item);
}
}
}
else {
MemberInfo[] members = element.GetType().GetMembers(BindingFlags.Public | BindingFlags.Instance);
WriteIndent();
Write(prefix);
bool propWritten = false;
foreach (MemberInfo m in members) {
FieldInfo f = m as FieldInfo;
PropertyInfo p = m as PropertyInfo;
if (f != null || p != null) {
if (propWritten) {
WriteTab();
}
else {
propWritten = true;
}
Write(m.Name);
Write("=");
Type t = f != null ? f.FieldType : p.PropertyType;
if (t.IsValueType || t == typeof(string)) {
WriteValue(f != null ? f.GetValue(element) : p.GetValue(element, null));
}
else {
if (typeof(IEnumerable).IsAssignableFrom(t)) {
Write("...");
}
else {
Write("{ }");
}
}
}
}
if (propWritten) WriteLine();
if (level < depth) {
foreach (MemberInfo m in members) {
FieldInfo f = m as FieldInfo;
PropertyInfo p = m as PropertyInfo;
if (f != null || p != null) {
Type t = f != null ? f.FieldType : p.PropertyType;
if (!(t.IsValueType || t == typeof(string))) {
object value = f != null ? f.GetValue(element) : p.GetValue(element, null);
if (value != null) {
level++;
WriteObject(m.Name + ": ", value);
level--;
}
}
}
}
}
}
}
}
private void WriteValue(object o)
{
if (o == null) {
Write("null");
}
else if (o is DateTime) {
Write(((DateTime)o).ToShortDateString());
}
else if (o is ValueType || o is string) {
Write(o.ToString());
}
else if (o is IEnumerable) {
Write("...");
}
else {
Write("{ }");
}
}
}
2015 Update
YAML also serves this purpose quite well, this is how it can be done with YamlDotNet
install-package YamlDotNet
private static void DumpAsYaml(object o)
{
var stringBuilder = new StringBuilder();
var serializer = new Serializer();
serializer.Serialize(new IndentedTextWriter(new StringWriter(stringBuilder)), o);
Console.WriteLine(stringBuilder);
}
回答2:
You could use the JSON serialiser, which should be easy to read for anyone use to working with JSON
User theUser = new User();
theUser.Name = "Joe";
System.Runtime.Serialization.Json.DataContractJsonSerializer serializer = new System.Runtime.Serialization.Json.DataContractJsonSerializer(myPerson.GetType());
MemoryStream ms = new MemoryStream();
serializer.WriteObject(ms, theUser );
string json = Encoding.Default.GetString(ms.ToArray());
回答3:
Updated 2019
You can find the ObjectDumper project on GitHub. You can also add it via Visual Studio via NuGet package manager.
回答4:
If you're working with markup, System.Web.ObjectInfo.Print (ASP.NET Web Pages 2) will accomplish this, nicely formatted for HTML.
For example:
@ObjectInfo.Print(new {
Foo = "Hello",
Bar = "World",
Qux = new {
Number = 42,
},
})
In a webpage, produces:
回答5:
Here's a visual studio extension I wrote to do this:
https://visualstudiogallery.msdn.microsoft.com/c6a21c68-f815-4895-999f-cd0885d8774f
in action:
回答6:
I know this is an old question, but thought I'd throw out an alternative that worked for me, took me about two minutes to do.
Install Newtonsoft Json.NET: http://james.newtonking.com/json
(or nuget version) http://www.nuget.org/packages/newtonsoft.json/
Reference Assembly:
using Newtonsoft.Json;
Dump JSON string to log:
txtResult.Text = JsonConvert.SerializeObject(testObj);
回答7:
You could write that very easily with a little bit of reflection. Something kind of like:
public void Print(object value, int depth)
{
foreach(var property in value.GetType().GetProperties())
{
var subValue = property.GetValue(value);
if(subValue is IEnumerable)
{
PrintArray(property, (IEnumerable)subValue);
}
else
{
PrintProperty(property, subValue);
}
}
}
You can write up the PrintArray and PrintProperty methods.
回答8:
I have a handy T.Dump() Extension method that should be pretty close to the results you're looking for. As its an extension method, its non-invasive and should work on all POCO objects.
Example Usage
var model = new TestModel();
Console.WriteLine(model.Dump());
Example Output
{
Int: 1,
String: One,
DateTime: 2010-04-11,
Guid: c050437f6fcd46be9b2d0806a0860b3e,
EmptyIntList: [],
IntList:
[
1,
2,
3
],
StringList:
[
one,
two,
three
],
StringIntMap:
{
a: 1,
b: 2,
c: 3
}
}
回答9:
If you don't feel like copying and pasting Chris S's code, the Visual Studio 2008 samples come with an ObjectDumper.
Drive:\Program Files\Microsoft Visual Studio 9.0\Samples\1033\LinqSamples\ObjectDumper
回答10:
Here is an alternative:
using System.Reflection;
public void Print(object value)
{
PropertyInfo[] myPropertyInfo;
string temp="Properties of "+value+" are:\n";
myPropertyInfo = value.GetType().GetProperties();
for (int i = 0; i < myPropertyInfo.Length; i++)
{
temp+=myPropertyInfo[i].ToString().PadRight(50)+" = "+myPropertyInfo[i].GetValue(value, null)+"\n";
}
MessageBox.Show(temp);
}
(just touching level 1, no depth, but says a lot)
回答11:
For most classes, you could use the DataContractSerializer
回答12:
I just came across a similar requirement in a Blazor project, and came up with the following very simple component to output an object's (and it's child objects') data to the screen:
ObjectDumper.razor:
@using Microsoft.AspNetCore.Components
@using Newtonsoft.Json
<div>
<button onclick="@DumpVMToConsole">@ButtonText</button>
<pre id="json">@_objectAsJson</pre>
</div>
@functions {
// This component allows the easy visualisation of the values currently held in
// an object and its child objects. Add this component to a page and pass in a
// param for the object to monitor, then press the button to see the object's data
// as nicely formatted JSON
// Use like this: <ObjectDumper ObjectToDump="@_billOfLadingVM" />
[Parameter]
private object ObjectToDump { get; set; }
[Parameter]
private string ButtonText { get; set; } = "Show object's data";
string _buttonText;
string _objectAsJson = "";
public void DumpVMToConsole()
{
_objectAsJson = GetObjectAsFormattedJson(ObjectToDump);
Console.WriteLine(_objectAsJson);
}
public string GetObjectAsFormattedJson(object obj)
{
return JsonConvert.SerializeObject(
value: obj,
formatting: Formatting.Indented,
settings: new JsonSerializerSettings
{
PreserveReferencesHandling = PreserveReferencesHandling.Objects
});
}
}
You then stick that somewhere on a Blazor page as follows:
<ObjectDumper ObjectToDump="@YourObjectToVisualise" />
Which then renders a button you can press to see the current values of the bound object:
I've stuck that in a GitHub repo: tomRedox/BlazorObjectDumper
来源：https://stackoverflow.com/questions/1347375/object-dumper-class