Demonstrates the use of pre-defined validation callback methods in Admin Page Framework.

admin-page-framework-demo-field-validation.php

<?php
/* Plugin Name: Admin Page Framework Demo - Field Validation */ 

if ( ! class_exists( 'AdminPageFramework' ) ) {
    include_once( dirname( dirname( __FILE__ ) ) . '/admin-page-framework/development/admin-page-framework.php' );
}
    
class APFDemo_FieldValidation extends AdminPageFramework {

	public function setUp() {
		
		$this->setRootMenuPage( __( 'Field Validation', 'admin-page-framework-demo-field-validation' ) );	// where to belong
		$this->addSubMenuItem(
			array(
				'title' => __( 'Field Validation', 'admin-page-framework-demo-field-validation' ),	// page and menu title
				'page_slug' => 'apf_demo_field_validation'	// page slug
			)
		);
			
		$this->addSettingSections(	
			array(
				'section_id'	=>	'text_section',	
				'page_slug'		=>	'apf_demo_field_validation',	
			)
		);
		
		$this->addSettingFields(
			'text_section',	// the target section ID
			array(	
				'field_id'		=>	'url',
				'title'			=>	__( 'URL', 'admin-page-framework-demo-field-validation' ),
				'type'			=>	'text',
				'default'		=>	'http://wordpress.org',
			),
			array(	
				'field_id'		=>	'alpanumeric',
				'title'			=>	__( 'Alpanumeric', 'admin-page-framework-demo-field-validation' ),
				'type'			=>	'text',
			),
			array(	
				'field_id'		=>	'no_html',
				'title'			=>	__( 'No HTML', 'admin-page-framework-demo-field-validation' ),
				'type'			=>	'textarea',
			),			
			array(	
				'field_id'	=>	'submit',
				'type'	=>	'submit',
			)
		);
		
	}
		
	/**
	 * The pre-defined validation callback method.
	 * 
	 * The following hooks are available:
	 *	- validation_{instantiated class name}_{field id} – [3.0.0+] receives the form submission value of the field that does not have a section. The first parameter: ( string|array ) submitted input value. The second parameter: ( string|array ) the old value stored in the database.
	 *	- validation_{instantiated class name}_{section_id}_{field id} – [3.0.0+] receives the form submission value of the field that has a section. The first parameter: ( string|array ) submitted input value. The second parameter: ( string|array ) the old value stored in the database.
	 *	- validation_{instantiated class name}_{section id} – [3.0.0+] receives the form submission values that belongs to the section.. The first parameter: ( array ) the array of submitted input values that belong to the section. The second parameter: ( array ) the array of the old values stored in the database.
	 *	- validation_{page slug}_{tab slug} – receives the form submission values as array. The first parameter: submitted input array. The second parameter: the original array stored in the database.
	 *	- validation_{page slug} – receives the form submission values as array. The first parameter: submitted input array. The second parameter: the original array stored in the database.
	 *	- validation_{instantiated class name} – receives the form submission values as array. The first parameter: submitted input array. The second parameter: the original array stored in the database.
	 */
	public function validation_APFDemo_FieldValidation_text_section( $aInput, $aOldInput ) {	// validation_{instantiated class name}_{section id}
		
		// Set a flag
		$_fIsValid = true;
		
		// Prepare an field error array.
		$_aErrors = array();
		
		// Use the debug method to see what are passed.
		// $this->oDebug->logArray( $aInput );
		
		// Check if a url is passed
		if ( isset( $aInput['url'] ) && ! filter_var( $aInput['url'], FILTER_VALIDATE_URL ) ) {
			
			$_fIsValid = false;

			// $variable[ 'sectioni_id' ][ 'field_id' ]
			$_aErrors['text_section']['url'] = __( 'The value must be a url:', 'admin-page-framework-demo-field-validation' ) . ' ' . $aInput['url'];			
			
		}
		
		// Check if the value is alphabetical & numeric 
		if ( isset( $aInput['alpanumeric'] )&& ! ctype_alnum( $aInput['alpanumeric'] ) ) {
			
			$_fIsValid  = false;
			
			// $variable[ 'sectioni_id' ][ 'field_id' ]
			$_aErrors['text_section']['alpanumeric'] = __( 'The value must be a alphabetic and numeric:', 'admin-page-framework-demo-field-validation' ) . ' ' . $aInput['url'];
			
		}
		
		// Sanitize the value - strip HTML tags
		$aInput['no_html'] = isset( $aInput['no_html'] ) ? $aInput['no_html'] : '';
		$aInput['no_html'] = strip_tags( $aInput['no_html'] );
		 
				
		// An invalid value is found.
		if ( ! $_fIsValid ) {
		
			// Set the error array for the input fields.
			$this->setFieldErrors( $_aErrors );		
			$this->setSettingNotice( __( 'There was something wrong with your input.', 'admin-page-framework-demo-field-validation' ) );
			return $aOldInput;
			
		}		
		
		return $aInput;
		
	}
    
}
new APFDemo_FieldValidation;