带有var文档的弹出消息

Question

I'm trying to make a form with pop up message where if the user doesn't fill up the input box nothing will happen and I'm done with that using required = "required" of input type number.

What I need is when the input box has been filled a message will pop up and says that the item is added when the button is clicked by the user.

Here's my code:

 <label style="color:#000000;">Qty:
 <input type="number" min="1" name="qty" required = "required" />



 SCRIPT:
 <script type="text/javascript">
 function myFunction()
 {
 var a=document.forms["abc"]["qty"].value;
 if (a!=null){
 alert("Item has been successfully added to your Cart");
  }
  }
  </script>




  echo '<td>'.'<input name="but" type="image" value="'.$row3['id'].'"      
  src="images/button.png"  onclick="myFunction()" />'.'</td>';

Answer 1

You have to use an id for your input tag.

    <label style="color:#000000;">Qty:
 <input type="number" min="1" id="qty" name="qty" required = "required" />



 function myFunction()
 {
 var a=document.forms["abc"]["qty"].value;
    if (a!=null && a!= ""){
     alert("Item has been successfully added to your Cart");
    }
 }

Also check for empty fields

Answer 2

您错过了函数myFunction中的形式名称-“ abc”-您通过以下方式调用element

var a=document.forms["abc"]["qty"].value;