Difference between 'Html.Validate' and 'Html.ValidateFor'

Question

Why do we use .Validate and .Validatefor in validation?

I am using that, but I am not getting any error message in the UI.

Code

<div>
    @{Html.BeginForm();}
    @Html.TextBoxFor(x => x.LastName, new { id = "txtLastName" })
    @{Html.Validate("LastName");}
    @{Html.ValidateFor(x=>x.LastName);}
    <input type="submit" id="btnSubmit" value="Submit" />
    @{Html.EndForm();}
</div>

Answer 1

This behavior is intentional. Both these helpers just register corresponding parameters for client-side validation, without actually showing any message should the validation fail. However this message can still be displayed in a ValidationSummary.

If you want to show the message specific to the field/parameter, you should use ValidationMessage or ValidationMessageFor instead:

@Html.ValidationMessage("LastName")
@Html.ValidationMessageFor(x=>x.LastName)