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# fieldexpression validator

## Description

Validates a field using an OGNL expression.

## Parameters

- `fieldName` - The field name this validator is validating. Required if using Plain-Validator Syntax otherwise not required.
- `expression` - The Ognl expression (must evaluate to a boolean) which is to be validated the stack.

## Examples

    <!-- Plain Validator Syntax -->
    <validators>
        <!-- Plain Validator Syntax -->
        <validator type="fieldexpression">
           <param name="fieldName">myField</param>
           <param name="expression"><![CDATA[#myCreditLimit > #myGirfriendCreditLimit]]></param>
           <message>My credit limit should be MORE than my girlfriend</message>
        <validator>

        <!-- Field Validator Syntax -->
        <field name="myField">
            <field-validator type="fieldexpression">
                <param name="expression"><![CDATA[#myCreditLimit > #myGirfriendCreditLimit]]></param>
                <message>My credit limit should be MORE than my girlfriend</message>
            </field-validator>
        </field>
    </vaidators>