Microsoft Enterprise Library 5.0 - Introduction to Validation Block

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <configSections>
    <section name="validation" type="Microsoft.Practices.EnterpriseLibrary.Validation.Configuration.ValidationSettings, Microsoft.Practices.EnterpriseLibrary.Validation, Version=5.0.414.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" requirePermission="true" />
  </configSections>
  <validation>
    <type name="ELValidation.Entities.BasicCustomer" defaultRuleset="BasicCustomerValidationRules"
      assemblyName="ELValidation, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null">
      <ruleset name="BasicCustomerValidationRules">
        <properties>
          <property name="CustomerNo">
            <validator type="Microsoft.Practices.EnterpriseLibrary.Validation.Validators.NotNullValidator, Microsoft.Practices.EnterpriseLibrary.Validation"
              negated="false" messageTemplate="Customer must have valid no"
              tag="CustomerNo" name="Not Null Validator" />
            <validator type="Microsoft.Practices.EnterpriseLibrary.Validation.Validators.StringLengthValidator, Microsoft.Practices.EnterpriseLibrary.Validation"
              upperBound="5" lowerBound="5" lowerBoundType="Inclusive" upperBoundType="Inclusive"
              negated="false" messageTemplate="Customer no must have {3} characters."
              tag="CustomerNo" name="String Length Validator" />
            <validator type="Microsoft.Practices.EnterpriseLibrary.Validation.Validators.RegexValidator, Microsoft.Practices.EnterpriseLibrary.Validation"
              pattern="[A-Z]{2}[0-9]{3}" options="None" patternResourceName=""
              patternResourceType="" messageTemplate="Customer no must be 2 capital letters and 3 numbers."
              messageTemplateResourceName="" messageTemplateResourceType=""
              tag="CustomerNo" name="Regex Validator" />
          </property>
        </properties>
      </ruleset>
    </type>
  </validation>
</configuration>