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pls do you know how to use hackshop(its an SQL injesction software pls pm @ danielmac1120@yahoo.com

The code below thows a Sys.ArgumentUndefinedException: Value cannot be undefined


Anyidea what is with it as is?

/// <reference name="MicrosoftAjax.js"/>

Type.registerNamespace('Ajax.UserControls');

Ajax.UserControls.ImagePreview = function(element) {
//initialize the base
Ajax.UserControls.ImagePreview.initializeBase(this, [element]);

// Initialize instance level fields
this._DefaultImage = null;
this._PreviewImage = null;
this._changeHandler = null;
this._TargetImageID = null;
}

Ajax.UserControls.ImagePreview.prototype = {
//call initialize on this first
initialize: function() {
debugger;
Ajax.UserControls.ImagePreview.callBaseMethod(this, 'initialize');
// Wire up handler for onmouseover
//var sdelegate = Function.createDelegate(this, this._changeHandler);
this._changeHandler = Function.createDelegate(this, this._onChange);
$addHandler(this.get_element(), 'change', this._changeHandler);
}, //end initialize

dispose: function() {
debugger;
$removeHandler(this.get_element(), 'change', this._changeHandler);
//$clearHandlers(this.get_element());
//Add custom dispose actions here
Ajax.UserControls.ImagePreview.callBaseMethod(this, 'dispose');
}, //end dispose

//Properties

//_defaultimage
get_DefaultImage: function() {
return this._DefaultImage;
},
set_DefaultImage: function(value) {
this._DefaultImage = value;
},
//_previewimageID
get_PreviewImage: function() {
return this._PreviewImage();
},

set_PreviewImage: function(value) {
if (value != this._PreviewImage) {
this._PreviewImage = value;
this.raisePropertyChanged('PreviewImage');
}
},
//_targetImageID
get_TargetImageID: function() {
return this._TargetImageID;
},
set_TargetImageID: function(value) {
this._TargetImageID = value;
},
// Event Handlers
_changeHandler: function(e) {
debugger;
var fileuploadcontrol = this.get_element();
if (fileuploadcontrol)
{
var filename = fileuploadcontrol.value;
if (filename != null)
{
// Get a ref to the image element
var imgcontrol = $get(this._TargetImageID);
//be sure there is an imagecontrol to work with
if (imgcontrol && !imgcontrol.disabled && imgcontrol.src != this.get_PreviewImage())
{
// Set the source to the preview image
imgcontrol.src = this.get_PreviewImage();
}
else
{
if (imgcontrol.src != this.get_DefaultImage)
{
//set it to the disabled image immediately
imgcontrol.src = this.get_DefaultImage();
}
}
}//end filename!=null
}
}

}
Ajax.UserControls.ImagePreview.registerClass('Ajax.UserControls.ImagePreview', Sys.UI.Behavior);

if (typeof (Sys) !== 'undefined') Sys.Application.notifyScriptLoaded();