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Validation

The MaskedTextBox provides a set of predefined mask rules and enables you to modify them.

If no mask is defined, the MaskedTextBox allows for any input.

Predefined Masks

The MaskedTextBox has a list of predefined mask rules which can be used to validate its user input.

The following example demonstrates how to set a zip code mask.

    @(Html.Kendo().MaskedTextBox()
          .Name("maskedtextbox")
          .Mask("00000-9999") // Set the zip code.
    )
  <kendo-maskedtextbox name="maskedtextbox" mask="00000-9999"></kendo-maskedtextbox>

Custom Masks

The MaskedTextBox enables you to define custom mask rules if none of the predefined ones is suitable. To add a custom rule, use the Rules method.

The MaskedTextBox supports JavaScript Regular Expressions defined as a string or a JavaScript function.

The following example demonstrates how to define a custom rule for the - (minus) and + (plus) symbols.

  @(Html.Kendo().MaskedTextBox()
        .Name("maskedtextbox")
        .Rules(rules => {
            rules.Add('~', "/[+-]/");
        })
        .Mask("~0000") // Set a mask with a custom rule.
   )
  @{
    var rules = new Dictionary<string, string>()
    {
        {"~", "/[+-]/"}
    };
  }

  <kendo-maskedtextbox name="maskedtextbox" rules="@rules" mask="~0000" ></kendo-maskedtextbox>

See Also

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