# ParameterConstraints
<a name="API_ParameterConstraints"></a>

A set of criteria that CloudFormation uses to validate parameter values. Although other constraints might be defined in the stack template, CloudFormation returns only the `AllowedValues` property.

## Contents
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 ** AllowedValues.member.N **   
A list of values that are permitted for a parameter.  
Type: Array of strings  
Required: No

## See Also
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For more information about using this API in one of the language-specific AWS SDKs, see the following:
+  [AWS SDK for C\$1\$1](https://docs.aws.amazon.com/goto/SdkForCpp/cloudformation-2010-05-15/ParameterConstraints) 
+  [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/cloudformation-2010-05-15/ParameterConstraints) 
+  [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/cloudformation-2010-05-15/ParameterConstraints)