创建表单元素时出现 Javascript 错误

Question

Error:

uncaught exception: [Exception... "Component returned failure code: 0x80004003 (NS_ERROR_INVALID_POINTER) [nsIDOMHTMLSelectElement.appendChild]" nsresult: "0x80004003 (NS_ERROR_INVALID_POINTER)" location: "JS frame:: http://localhost/midas/index.php/submit/displayform :: :: line 104" data: no]

The code is meant to create:

textboxt - textbox - textbox - pulldown - textbox

Here is the code below

<script type="text/javascript">
<!--
  var ta=new Array();
  var n=15;
window.onload=function()
{
   inp=document.getElementsByTagName('input');
for(c=0;c<inp.length;c++) 
    {
        if(inp[c].value=='add') 
        {
           inp[c].onclick=function() 
            {
                var ta = [];
                var n = 15;

               ta[n]=document.createElement('input');
               ta[n].setAttribute('rows',1);
               ta[n].setAttribute('cols',20);
               ta[n].name='time'+n;
               document.getElementById('txtara').appendChild(ta[n])
               ta[n]=document.createElement('input');
               ta[n].setAttribute('rows',1);
               ta[n].setAttribute('cols',20);
               ta[n].name='event'+n;
               document.getElementById('txtara').appendChild(ta[n])
               ta[n]=document.createElement('input');
               ta[n].setAttribute('rows',1);
               ta[n].setAttribute('cols',20);
               ta[n].name='supplies'+n;
               document.getElementById('txtara').appendChild(ta[n])

                var sel = document.createElement('select');



                ta[n]=document.createElement('option');
                ta[n].value = 'YES';
                ta[n].name='success'+n;
                ta[n].innerHTML = ta[n].value;
                n++;
                ta[n]=document.createElement('option');
                ta[n].value = 'NO';
                ta[n].name='success'+n;
                ta[n].innerHTML = ta[n].value;
                n++;

                sel.appendChild(ta[0]);
                sel.appendChild(ta[1]);


                document.getElementById('txtara').appendChild(sel);



               document.getElementById('here').appendChild(sel);
               document.getElementById('txtara').appendChild(ta[n])
               n++;
            }
         }

    }
}
//-->
</script>

Answer 1

Your code is creating nodes and storing them in ta[15] and ta[16] , but you're inserting nodes from ta[0] and ta[1] into the DOM, which don't exist.

do var n = 0 ; instead of n = 15 .