httpObject.onreadystatechange passing a variable to function - type mismatch error

[Chris Huber]

I'm trying to create a generic AJAX function that has the data field passed to the function in order to return the results to the proper place.

Oddly enough, this does not work if I comment out the 'alert' line in the set_output, however it does work if I have it pop up those variables.

Either way, I do still get a type-mismatch on the line:

httpObject.onreadystatechange = setOutput(error_output, field_output);

I figure that is because you shouldn't pass variables to a function in this way.

 
function doWork(error_output, field_output){
 error_outputx=document.getElementById(error_output);
 field_outputx=document.getElementById(field_output);
 httpObject = getHTTPObject();
 if (httpObject != null) {
  if(document.body.textContent){ //firefox does not support innerText and IE does not support textContent
   httpObject.open("GET", "people_picker_server.php?inputText="+field_outputx.textContent, true);
  } else if(document.body.innerText) {
   httpObject.open("GET", "people_picker_server.php?inputText="+field_outputx.innerText, true);
  }
  httpObject.send(null);
  httpObject.onreadystatechange = setOutput(error_output, field_output);
 }
}

function setOutput(error_output, field_output){
 //alert(error_output + " " + field_output);
 error_outputx=document.getElementById(error_output);
 field_outputx=document.getElementById(field_output);
 if(httpObject.readyState == 4){
  var results = eval('(' + httpObject.responseText + ')');
  field_outputx.focus();
  field_outputx.innerHTML = results.sendback;
  error_outputx.innerHTML = results.error_list;
 }
}

Any suggestions would be greatly appreciated!

[Eric Pascarello]

what would you expect from this script

function foo(){
return "hi";
}

var x = foo();

alert(x);

now what do you expect
httpObject.onreadystatechange = setOutput(error_output, field_output); to do compared with var x = foo()?

You need to use a closure.

Eric

[Chris Huber]

I'm new to closures, but I understand what that example script does. I'm not sure how to apply it to my script.

[Eric Pascarello]

r...s...c... = function(){ yourcode }

Eric

[Chris Huber]

Ok, now I got it. Thanks - works great!