Email validation in Gravity Forms - validate an email address entered in a regular text input

gf-email-validate.php

<?

	/**
	 * Hooks for validating an email address in Gravity Forms
	 * When using a plain text input to collect an email, this will validate that the email address entered is a proper email address
	 * Useful for situations in which the existing gravity forms email field can't be used
	 *
	 * Change line 28 and line 37 to adapt this to your form
	 *
	 * @package d7
	 * @subpackage boilerplate-theme
	 *
	 * @param array $validation_result  Contains the form data Gravity Forms passes at this point
	 *
	 */

	// Validate the email field
	// Since we are using the gravity forms post fields, we can't use the default gravity forms email validation
	add_filter('gform_validation', 'custom_validation');
	function custom_validation($validation_result){

		// Set the $validation_result object to $form for clarity
	    $form = $validation_result["form"];

	    // Get the value the user entered for the email field
	    // EDIT HERE WITH THE INPUT NAME OF YOUR FIELD (input_2 is the name attribute of the input field)
	    $email = $_POST["input_2"];

	    if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {

	    	// set the form validation to false
	    	$validation_result["is_valid"] = false;

	    	// specify the invalid field and provide custom validation message
	    	// EDIT HERE WITH THE ZERO INDEXED NUMBER OF THE FIELD (in thise case $form["fields"][2], because the field is the third field in the form)
	    	$form["fields"][2]["failed_validation"] = true;
	    	$form["fields"][2]["validation_message"] = 'Please enter a valid email address';

	    }

	    // update the form in the validation result with the form object you modified
	    $validation_result["form"] = $form;

	    return $validation_result;

	}

Thank You!

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    if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {

    	// set the form validation to false
    	$validation_result["is_valid"] = false;

		foreach ($form['fields'] as &$field) {
			if ($field->id == 2) { //input id
				$field->failed_validation = true;
				$field->validation_message = 'Please enter a valid email address';
			}
		}

    }

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