Contact Form 7 Phone Number Validation

========================= contact-form-7/modules/text.php

insert this code:

 wpcf7_add_shortcode( 'digit', 'wpcf7_text_shortcode_handler', true );  
 wpcf7_add_shortcode( 'digit*', 'wpcf7_text_shortcode_handler', true );  

after this:

 wpcf7_add_shortcode( 'email*', 'wpcf7_text_shortcode_handler', true );  

insert this code:

 if ( 'digit' == $type || 'digit*' == $type )  
 $class_att .= ' wpcf7-validates-as-digit';  

after this:

 if ( 'text*' == $type || 'email*' == $type )  
 $class_att .= ' wpcf7-validates-as-required';  

insert this code:

 add_filter( 'wpcf7_validate_email*', 'wpcf7_text_validation_filter', 10, 2 );  
 add_filter( 'wpcf7_validate_digit*', 'wpcf7_text_validation_filter', 10, 2 );  

after this:

 add_filter( 'wpcf7_validate_email', 'wpcf7_text_validation_filter', 10, 2 );  

insert this code:

 if ( 'digit' == $type || 'digit*' == $type ) {  
 if ( '' == $_POST[$name] ) {  
 $result['valid'] = false;  
 //$result['reason'][$name] = $wpcf7_contact_form->message( 'invalid_required' );  
 $result['reason'][$name] = wpcf7_get_message( 'invalid_required' );  
 } elseif ( '' != $_POST[$name] && ! is_telnum( $_POST[$name] ) ) {  
 $result['valid'] = false;  
 //$result['reason'][$name] = $wpcf7_contact_form->message( 'invalid_digit' );  
 $result['reason'][$name] = wpcf7_get_message( 'invalid_digit' );  
 }  
 }  

after this code:

 if ( 'email' == $type || 'email*' == $type ) {  
 if ( 'email*' == $type && '' == $_POST[$name] ) {  
 $result['valid'] = false;  
 $result['reason'][$name] = $wpcf7_contact_form->message( 'invalid_required' );  
 } elseif ( '' != $_POST[$name] && ! is_email( $_POST[$name] ) ) {  
 $result['valid'] = false;  
 $result['reason'][$name] = $wpcf7_contact_form->message( 'invalid_email' );  
 }  
 }  

================== contact-form-7/includes/functions.php to add the error message for the telephone number validation.

insert this code:

 'invalid_digit' => array(  
 'description' => __( "There is a field that sender is needed to fill in with numbers", 'wpcf7' ),  
 'default' => __( 'Please fill the required field with numbers.', 'wpcf7' )  
 )  

after this code:

 'invalid_required' => array(  
 'description' => __( "There is a field that sender is needed to fill in", 'wpcf7' ),  
 'default' => __( 'Please fill the required field.', 'wpcf7' )  
 ),  

===========================wp-includes/formatting.php and create a new function

 function is_telnum($telnum)  
 {  
 //$regexp = '/^[0-9\+\-]{7,}$/';  
 //$regexp = '/^[0-9]{1,}/';//numeric  
 $regexp = '/^[0-9\+\-\)\(\d\s]{7,}$/';  
 if(preg_match($regexp, $telnum))  
 return true;  
 else  
 return false;  
 }  

=========

 Your Phone [digit* text-123]