In Grails, how do I display validation error messages next to the fields?

问题

The Grails 2.0.4 documentation for validation shows you how to display error messages at the top of the page and how to add a css class to an element if a field is invalid, but it doesn't tell you how to display the error message next to the fields themselves, something like this:

      -----------------------
Name: |                     |  You must enter a name!
      -----------------------

How do you retrieve the specific error message for an invalid field and then display it next to the field it's for?

回答1:

Actually, the documentation does show how to do this, it just isn't overly clear that this is what they mean:

<g:renderErrors bean="${book}" as="list" field="title"/>

If you specify the field attribute, it will only render error(s) for that field. So then it is just up to you to write the HTML accordingly.

<input type="text" ... /> <g:if test="${bean.hasErrors}"><g:renderErrors bean="${book}" as="list" field="title"/></g:if>

It can get as simple or as complicated as you would like it and while I generally like grails plugins, this just seems simple enough to do without one and you have more control over the markup.

回答2:

I use the Grails Fields plugin to do this, and it works a treat.

It makes it easy to create default templates for form field rendering. For example I have the following in grails-app/views/_fields/default/_field.gsp:

<%@ page defaultCodec="html" %>
<div class="control-group${invalid ? ' error' : ''}">
    <label class="control-label" for="${property}${index ?: ""}">${label}</label>
    <div class="controls">
        <%= widget.replace("id=\"${property}\"", "id=\"${property}${index ?: ""}\"") %>
        <g:if test="${invalid}"><span class="help-inline">${errors.join('<br>')}</span></g:if>
    </div>
</div>

As you can see from the HTML the errors are displayed inline. Here is part of my login form:

<g:form controller="home" action="login" >
    <f:field bean="user" property="email"/>
    <f:field bean="user" property="password">
        <g:field type="password" name="${property}" value="${value}"/>
    </f:field>
</g:form>

回答3:

Here is the custom error in context, wrapped around username field. This will do what you want.

<dt>User Id</dt>
            <dd><g:textField name="username" value="${user?.username}"/>
            <g:hasErrors bean="${user}" field="username">
                    <g:eachError bean="${user}" field="username">
                        <p style="color: red;"><g:message error="${it}"/></p>
                    </g:eachError>
                </g:hasErrors>
            </dd>

回答4:

I would recommend going with Jquery validation plugin. There's several Grails plugin about this, but they are a bit out-dated. Besides, I think this task is pretty simple for using another plugin.

来源：https://stackoverflow.com/questions/10943684/in-grails-how-do-i-display-validation-error-messages-next-to-the-fields

标签

validation

grails

grails-2.0