How to add a new validation rule to mvcClientValidationMetadata?

问题

I have a form with two fields that need to be equal (password and password confirmation). I've created a class attribute to check that and on server side it works great. On the client side it does nothing. I need the message to appear in ValidationSummary ("Password repeated" needs to be the same as "Password").

I realized that the easiest way to check these fields would be adding the rule manually to window.mvcClientValidationMetadata. I was trying to do that but nothing worked.

My code:

<% using (Html.BeginForm("ResetPassword", "Account", FormMethod.Post}))
   { %>
<%= Html.ValidationSummary() %>
    <div>
        <%= Html.ValidationMessageFor(m => m.Email)%>
        <%= Html.LabelFor(m => m.Email)%>
    </div>
    <div>
        <%= Html.TextBoxFor(m => m.Email)%>
        <% Html.ValidateFor(m => m.Email);%>
    </div>
    <div>
        <%= Html.ValidationMessageFor(m => m.PasswordModel.Password)%>
        <%= Html.LabelFor(m => m.PasswordModel.Password)%>
    </div>
    <div>
        <%= Html.PasswordFor(m => m.PasswordModel.Password)%>
    </div>
    <div>
        <%= Html.ValidationMessageFor(m => m.PasswordModel.PasswordRepeated)%>
        <%= Html.LabelFor(m => m.PasswordModel.PasswordRepeated)%>
    </div>
    <div>
        <%= Html.PasswordFor(m => m.PasswordModel.PasswordRepeated)%>
    </div>
    <div>
        <%= Html.ValidationMessageFor(m => m.PasswordModel.PasswordRepeated)%>
        <%= Html.LabelFor(m => m.PasswordModel.PasswordRepeated, true)%>
    </div>
<% } %>

Html.EnableClientValidation method is executed before this form is generated.

Below you'll find the solution to my problem.

回答1:

The worst thing you may do is to execute exacly the same code - you'll overwrite the existing rules.

To add validation rules you need to put this code right after <% } %> closing using(... of your BeginForm:

<% } %>

<script type="text/javascript">

    window.mvcClientValidationMetadata[0]["Fields"].push( //check if the '0' is number corresponding to your form validation metadata
      {
          "FieldName": "PasswordModel.PasswordRepeated", // name attribute of the element
          "ReplaceValidationMessageContents": false,
          "ValidationMessageId": "PasswordModel_PasswordRepeated_validationMessage", //id of the ValidationMessageFor (if needed)
          "ValidationRules":
          [
            {
                "ErrorMessage": 'Password repeated needs to be the same as Password',
                "ValidationParameters": "#PasswordModel_Password", //'params' parameter in your validation function, can be an object
                "ValidationType": "propertiesMustMatch" //name of the validation function placed in $.validator.methods
            }
          ]
      }
    );

</script>

propertiesMustMatch function checks if given fields are equal (jQuery equalTo didin't work correctly in our system).

There is no "Uncaught TypeError: Cannot call method 'push' of undefined" exception, because mvcClientValidationMetadata is generated in <script> element put where <% } %> is.

来源：https://stackoverflow.com/questions/13379339/how-to-add-a-new-validation-rule-to-mvcclientvalidationmetadata