The asp-validation-summary-tag helper displays a list of validation error messages for a given property. This tag is used for properties of the DIV element. The validation error message is weakly typed and displays if the specified field, property, or data annotations attribute is invalid. This helper can be found at the top of a page. In addition to displaying validation messages, this tag helps you keep track of any errors that occur.
The validation summary tag helps you show a summary of errors that occur during form validation. This summary is displayed in an unordered list. You can also add your own custom error message by using the ModelState.AddModelError() method. To display all error messages, you can also use the ValidationSummary() function. The Validation-summary tag helper is used when you want to display all errors pertaining to the ModelState.
Validation summary tag helper displays an unordered list of validation errors. The value of asp-validation-summary is an array of validation error messages. The error messages are displayed in red on the div. The asp-validation-for tag helper displays validation errors on the model level, instead of displaying error messages per field. The model-level error messages are applicable to a model’s whole data or individual properties.
The validation summary tag helper works in a similar way to input tag helpers, but uses the text-area or label tag. Instead of rendering the whole form, the validation summary tag helper generates a div with the asp-validation-summary attribute. When used in a page with a form, this tag helps to show a field-level error message and a summary message. Asp-validation-summary tag helper will display error messages next to the input element, while the asp-for attribute will output the message in a span tag.
The ValidationSummary control displays a list of validation errors in one convenient location. This is especially useful for large forms, where users might accidentally enter invalid values at the end of the form without seeing an error message. The validation summary control displays a list of validation issues at the top of your form. This makes it easy to see. You can also customize the text and display of the form with this control.
Tag helpers are similar to HTML helpers in that they allow server-side code to participate in the rendering of HTML. Both are written in C#, and target HTML elements based on their name or attribute. In the case of the LabelTagHelper, for example, the helper will target an HTML label when its attributes are applied. Tag helpers, unlike HTML, reduce the number explicit transitions between HTML and C#.