php - Javascript regex email validation -

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• how validate email address in javascript? 65 answers

i have used regex test email input. give alert when wrong email (for eg without @ or .com) submitted when press ok alert, still posts email email address directed page send_msg.php when should not.. quite new javascript , php still learning.. know if clause should follow else don't know how make post email if true. , can how make display message below email input field instead of making raise alert?

<script> function checkemail(inputvalue){     var pattern=/^([a-za-z0-9_.-])+@([a-za-z0-9_.-])+\.([a-za-z])+([a-za-z])+/; if(pattern.test!=(inputvalue)){            alert("please enter valid email address");            return false;   } 

}

<form id="contact-form" name= "form1 "action="send_msg.php" method="post">         <h3>get in touch</h3>         <h4>fill in form below, , we'll within 24 hours.</h4>         <div>             <label>                 <span>name: </span>                 <input placeholder="please enter name" name="name" type="text" tabindex="1" required autofocus>             </label>         </div>         <div>             <label>                 <span>email: </span>                 <input placeholder="please enter email address" name="email" type="email" tabindex="2" required>             </label>         </div>          <div>             <label>                 <span >message: </span>                 <textarea placeholder="include details can" name="message" tabindex="5" size= "35" maxlength= "255"></textarea>             </label>         </div>         <div>             <button name="submit" type="submit" onclick="checkemail(document.contact-form.email.value)" id="contact-submit">send email</button>         </div>     </form> 

assuming regex validation ok, can prevent form submit, doing this:

<form onsubmit="return checkemail(document.contact-form.email.value);" id="contact-form" name= "form1 "action="send_msg.php" method="post"> ... </form> 

and remove onclick submit button. if regex function returns true if valid , false if not valid, form submit when email input has valid data in it.

hope helps.

let me know.

cheers!