php - having issues to validate form using JavaScript -

on form when enter email address correctly , leaves name field blank, page submitting , javacript not running. otherwise working fine.

please me solve javascript.

function validateform(data) {     var validfield = "";     var namevalid=/^[a-za-z ]+$/;     if(data.name.value == ""){validfield += "- please enter name\n";}     else if(data.name.value.search(namevalid)==-1){validfield += "- entered name contains numbers or symbols\n";}     if (/^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/.test(data.email.value)){         return true;         }         validfield += "- please enter valid e-mail address\n";         alert(validfield);         return false; }   <form name="data" onsubmit="return validateform(this);" action="some.php" method="post"> <div> <label>name:</label><input type="text" id="name" name="name" size="20"  maxlength="20"/></div>  <div> <label>e- mail address:</label><input type="text" id="email" name="email" size="20"  maxlength="30"/></div>  <input type="submit" name="submit" value="start now!"/> </form> 

you need refactor code little bit. @ minute if email address valid return true out of function regardless of name field.

function validateform(data) {     var validfield = "";     var isvalid = false;     var namevalid = /^[a-za-z ]+$/;     if (data.name.value == "") {         validfield += "- please enter name\n";     }     else if (data.name.value.search(namevalid) == -1) {          validfield += "- entered name contains numbers or symbols\n";          }     if (!(/^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/.test(data.email.value))) {         validfield += "- please enter valid e-mail address\n";     };     if (validfield == "") {         isvalid = true;     }     if (!isvalid) {         alert(validfield);     }     return isvalid; }