Repeat section of code. 1

[bdichiara]

I have a section of code that I need to repeat in other functions. To save space and make things cleaner, i tried putting the section that repeats in it's own function, but i'm getting an error and my code isn't executing.

This the entire code:

function getLinks(){
  var xmlhttp=false; //Clear our fetching variable
    try {
    xmlhttp = new ActiveXObject('Msxml2.XMLHTTP');
  }
  catch (e) {
    try {
      xmlhttp = new
      ActiveXObject('Microsoft.XMLHTTP');
    }
    catch (E) {
      xmlhttp = false;
    }
  }
  if (!xmlhttp && typeof XMLHttpRequest!='undefined') {
    xmlhttp = new XMLHttpRequest();
  }
  var file = 'blah_inc.php?links';
  xmlhttp.open('GET', file, true);
  xmlhttp.onreadystatechange=function() {
    if (xmlhttp.readyState==4) {
      var content = xmlhttp.responseText;
      if( content ){
        document.getElementById('links').innerHTML = content;
      }
    }
  }
  xmlhttp.send(null)
  return;
}

I have several other functions similar to this and this part is repeated in all of them:

var xmlhttp=false; //Clear our fetching variable
  try {
  xmlhttp = new ActiveXObject('Msxml2.XMLHTTP');
}
catch (e) {
  try {
    xmlhttp = new
    ActiveXObject('Microsoft.XMLHTTP');
  }
  catch (E) {
    xmlhttp = false;
  }
}
if (!xmlhttp && typeof XMLHttpRequest!='undefined') {
  xmlhttp = new XMLHttpRequest();
}

Is there a reason why I can't just put that in a function (called preAjax(); and just put it in each, like this:

function preAjax(){
  var xmlhttp=false; //Clear our fetching variable
    try {
    xmlhttp = new ActiveXObject('Msxml2.XMLHTTP');
  }
  catch (e) {
    try {
      xmlhttp = new
      ActiveXObject('Microsoft.XMLHTTP');
    }
    catch (E) {
      xmlhttp = false;
    }
  }
  if (!xmlhttp && typeof XMLHttpRequest!='undefined') {
    xmlhttp = new XMLHttpRequest();
  }
}

function getLinks(){
  preAjax();
  var file = 'blah_inc.php?links';
  xmlhttp.open('GET', file, true);
  xmlhttp.onreadystatechange=function() {
    if (xmlhttp.readyState==4) {
      var content = xmlhttp.responseText;
      if( content ){
        document.getElementById('links').innerHTML = content;
      }
    }
  }
  xmlhttp.send(null)
  return;
}

_______________
_brian.

 

[kaht]

The problem is that xmlhttp is defined in your preajax function and is local to that function only, so the rest of the getlinks function does not know what xmlhttp is. The solution to this is the following:

function preAjax(){
  var xmlhttp=false; //Clear our fetching variable
    try {
    xmlhttp = new ActiveXObject('Msxml2.XMLHTTP');
  }
  catch (e) {
    try {
      xmlhttp = new
      ActiveXObject('Microsoft.XMLHTTP');
    }
    catch (E) {
      xmlhttp = false;
    }
  }
  if (!xmlhttp && typeof XMLHttpRequest!='undefined') {
    xmlhttp = new XMLHttpRequest();
  }
  [!]return xmlhttp[/!]
}

function getLinks(){
  [!]var xmlhttp = [/!]preAjax();
  var file = 'blah_inc.php?links';
  xmlhttp.open('GET', file, true);
  xmlhttp.onreadystatechange=function() {
    if (xmlhttp.readyState==4) {
      var content = xmlhttp.responseText;
      if( content ){
        document.getElementById('links').innerHTML = content;
      }
    }
  }
  xmlhttp.send(null)
  return;
}

-kaht

http://www.silkypups.com

[small](All puppies have now found loving homes, thanks for all who showed interest)[/small]

 

[bdichiara]

excellent. thanks!

_______________
_brian.