source/core-developers/email-validator.md

---
layout: default
title: email validator
parent:
    title: Validation
    url: validation.html
---

# email validator
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* Will be replaced with the ToC, excluding a header
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## Description

EmailValidator checks that a given String field, if not empty, is a valid email address.

The regular expression used to validate that the string is an email address is:

```
\\b^['_a-z0-9-\\+]+(\\.['_a-z0-9-\\+]+)*@[a-z0-9-]+(\\.[a-z0-9-]+)*\\.([a-z]{2,6})$\\b
```

> This Regex can change, please always check it in the [source code](https://github.com/apache/struts/blob/main/core/src/main/java/org/apache/struts2/validator/validators/EmailValidator.java#L83)

You can also specify `expression`, `caseSensitive` and `trim` params as a OGNL expression, see the example below.

## Parameters

- `fieldName` - The field name this validator is validating. Required if using Plain-Validator Syntax otherwise not required.

Check also documentation of the `RegexpValidator` for more details - the EmailValidator is based on it.

> Warning: do not use `${regexExpression}`, `${caseSensitiveExpression}` and `${trimExpression}` as an expression 
> as this will turn into infinitive loop!

## Examples

```xml
<!-- Plain Validator Syntax -->
<validators>
    <validator type="email">
        <param name="fieldName">myEmail</param>
        <message>Must provide a valid email</message>
    </validator>
</validators>
 
<!-- Field Validator Syntax -->
<field name="myEmail">
   <field-validator type="email">
      <message>Must provide a valid email</message>
   </field-validator>
</field>
 
<!-- Field Validator Syntax with expressions -->
<!-- Only available when used with xml based configuration, if you want to have the same
        flexibility with annotations use @RegexFieldValidator instead -->
<field name="myEmail">
   <field-validator type="email">
      <param name="regexExpression">${emailPattern}</param> <!-- will be evaluated as: String getEmailPattern() -->
      <param name="caseSensitiveExpression">${emailCaseSensitive}</param> <!-- will be evaluated as: boolean getEmailCaseSensitive() -->
      <param name="trimExpression">${trimEmail}</param> <!-- will be evaluated as: boolean getTrimEmail() -->
      <message>Must provide a valid email</message>
   </field-validator>
</field>
```