Required field(s) validation v1.10- By NavSurf

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<pre><script language="JavaScript">
<!--

/***********************************************
* Required field(s) validation v1.10- By NavSurf
* Visit Nav Surf at http://navsurf.com
* Visit http://www.dynamicdrive.com/ for full source code
***********************************************/

function formCheck(formobj){
 // Enter name of mandatory fields
 var fieldRequired = Array("FirstName", "LastName");
 // Enter field description to appear in the dialog box
 var fieldDescription = Array("First Name", "Last Name");
 // dialog message
 var alertMsg = "Please complete the following fields:\n";

 var l_Msg = alertMsg.length;

 for (var i = 0; i < fieldRequired.length; i++){
  var obj = formobj.elements[fieldRequired[i]];
  if (obj){
   switch(obj.type){
   case "select-one":
    if (obj.selectedIndex == -1 || obj.options[obj.selectedIndex].text == ""){
     alertMsg += " - " + fieldDescription[i] + "\n";
    }
    break;
   case "select-multiple":
    if (obj.selectedIndex == -1){
     alertMsg += " - " + fieldDescription[i] + "\n";
    }
    break;
   case "text":
   case "textarea":
    if (obj.value == "" || obj.value == null){
     alertMsg += " - " + fieldDescription[i] + "\n";
    }
    break;
   default:
   }
   if (obj.type == undefined){
    var blnchecked = false;
    for (var j = 0; j < obj.length; j++){
     if (obj[j].checked){
      blnchecked = true;
     }
    }
    if (!blnchecked){
     alertMsg += " - " + fieldDescription[i] + "\n";
    }
   }
  }
 }

 if (alertMsg.length == l_Msg){
  return true;
 }else{
  alert(alertMsg);
  return false;
 }
}
// -->
</script>



&lt;!--SAMPLE FORM --------------------------------&gt;

<form name="formcheck" onsubmit="return formCheck(this);">
First Name: <input name="FirstName" size="25" type="text" />
Last Name: <input name="LastName" size="25" type="text" />
<input type="submit" value="Submit Form" />
</form>
</pre>