String Length Validator

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Class Name: StringLengthValidator

Attribute Name: StringLengthValidatorAttribute

Configuration tool name: String Length Validator

Description

This validator checks that the length of the string is within the specified interval. The interval may include or exclude the endpoints. The lower or upper bound of the interval can be omitted.

Properties

The following table lists the String Length Validator properties.

String Length Validator Properties

Property

Description

LowerBound

This is the low-range boundary value. It must be of type Integer. The compiler checks this requirement if you directly invoke the validator in your code.

LowerBoundType

This property determines how to evaluate the LowerBound value. Possible values for LowerBoundType are Ignore, Inclusive, and Exclusive. The Ignore value means that the validator ignores the LowerBound value. This is the default. The Inclusive value means that the validator allows values that are equal to the LowerBound value. The Exclusive value means that the validator does not allow values that are equal to the LowerBound value.

Negated

This is a Boolean property. If it is set to True, it changes the validator's behavior so that it will fail if the condition is met, rather than when it is not met. The default is False.

Tag

This property is a user-supplied string. Typically, it is used to sort or categorize validation results that are in a log.

UpperBound

This is the upper-range boundary value. It must be type Integer. The compiler checks this requirement if you directly invoke the validator in your code.

UpperBoundType

This property determines how to evaluate the UpperBound value. Possible values for LowerBoundType are Ignore, Inclusive, and Exclusive. The Ignore value means that the validator ignores the UpperBound value. This is the default. The Inclusive value means that the validator allows values that are equal to the UpperBound value. The Exclusive value means that the validator does not allow values that are equal to the UpperBound value.

MessageTemplate

This property is a user-supplied string. Typically, it describes the validation result and is intended for a log.

MessageTemplateResourceName

If you do not want to use the MessageTemplate property to specify a message, you can use another template by specifying it with the MessageTemplateResourceName value. If you include both a MessageTemplate value and a MessageTemplateResourceName value, the MessageTemplate value takes precedence.

MessageTemplateResourceTypeName

If you specify a MessageTemplateResourceName value then you must specify a MessageTemplateResourceTypeName value, which is the type of the template you want to use.

Message Template Tokens

If the message template contains tokens (for instance, "{0}"), the validator will replace these tokens with values when the ValidationResult is created. The tokens supported by the RangeValidator are as follows:

Token

Meaning

{0}

The value being validated.

{1}

The Key of the value being validated.

{2}

The Tag of the validator instance.

{3}

The lower bound configured for the validator instance.

{4}

The lower bound type (Inclusive, Exclusive, or Ignore) configured for the validator instance.

{5}

The upper bound configured for the validator instance.

{6}

The upper bound type (Inclusive, Exclusive or Ignore) configured for the validator instance.

Examples

The following examples show how to use the validator with attributes .

Attributes

The following code example checks that the product code is a string between 1 and 10 characters long.

public class Product
{
   [StringLengthValidator(1, 10)]
   public string ProductCode
   {
      get
      {
         return productCode;
      }
   }
   // ...
}

'Usage
Public Class Product
    <StringLengthValidator(1, 10)> _
    ReadOnly Property ProductCode(ByVal _productCode As String)
        Get
            Return _productCode
        End Get
    End Property
End Class
Retired Content

This content is outdated and is no longer being maintained. It is provided as a courtesy for individuals who are still using these technologies. This page may contain URLs that were valid when originally published, but now link to sites or pages that no longer exist.
The latest Enterprise Library information can be found at the Enterprise Library site.