HtmlHelper<TModel>.ValidationMessageFor<TResult> Method
Definition
Important
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Returns the validation message if an error exists in the ModelStateDictionary
object for the specified expression
.
public:
generic <typename TResult>
virtual Microsoft::AspNetCore::Html::IHtmlContent ^ ValidationMessageFor(System::Linq::Expressions::Expression<Func<TModel, TResult> ^> ^ expression, System::String ^ message, System::Object ^ htmlAttributes, System::String ^ tag);
public Microsoft.AspNetCore.Html.IHtmlContent ValidationMessageFor<TResult> (System.Linq.Expressions.Expression<Func<TModel,TResult>> expression, string message, object htmlAttributes, string tag);
abstract member ValidationMessageFor : System.Linq.Expressions.Expression<Func<'Model, 'Result>> * string * obj * string -> Microsoft.AspNetCore.Html.IHtmlContent
override this.ValidationMessageFor : System.Linq.Expressions.Expression<Func<'Model, 'Result>> * string * obj * string -> Microsoft.AspNetCore.Html.IHtmlContent
Public Function ValidationMessageFor(Of TResult) (expression As Expression(Of Func(Of TModel, TResult)), message As String, htmlAttributes As Object, tag As String) As IHtmlContent
Type Parameters
- TResult
The type of the expression
result.
Parameters
- expression
- Expression<Func<TModel,TResult>>
An expression to be evaluated against the current model.
- message
- String
The message to be displayed. If null
or empty, method extracts an error string from the
ModelStateDictionary object. Message will always be visible but client-side
validation may update the associated CSS class.
- htmlAttributes
- Object
An Object that contains the HTML attributes for the tag
element.
Alternatively, an IDictionary<TKey,TValue> instance containing the HTML attributes.
- tag
- String
The tag to wrap the message
in the generated HTML. Its default value is
ValidationMessageElement.
Returns
A new IHtmlContent containing the tag
element. null
if the
expression
is valid and client-side validation is disabled.