ajaxcallobject.js

一个AJAX框架

__AJAXCboList = new Array();
__PageForm = null;
__bPageIsStored = false;
__bUnloadStoredPage = false;
__bTracing = false;
__doingSubmit = false;
__PreviousPostBack = null;
__TraceWindows = new Array();
__ClockID = 0;
__IsOpera = false;
__IsIE = false;
__ClkEvent = null;

// Excluding from post flags
// To be used with the "ExcludeFlags" attribute
excfViewState = 1;
excfFingerprints = 2;
excfUserHidden = 4;
excfAllHidden = excfViewState | excfFingerprints | excfUserHidden;
excfFormElements = 8;
excfAllElements = excfAllHidden | excfFormElements;

function AjaxCallObject()
{
  this.Init();
}

AjaxCallObject.prototype.Init = function()
{
  this.XmlHttp = this.GetHttpObject();
}
 
AjaxCallObject.prototype.GetHttpObject = function()
{ 
  var xmlhttp;
  /*@cc_on
  @if (@_jscript_version >= 5)
    try {
      xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");
    } catch (e) {
      try {
        xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
      } catch (E) {
        xmlhttp = false;
      }
    }
  @else
  xmlhttp = false;
  @end @*/
  if (!xmlhttp && typeof XMLHttpRequest != 'undefined') {
    try {
      xmlhttp = new XMLHttpRequest();
    } catch (e) {
      xmlhttp = false;
    }
  }
  return xmlhttp;
}

AjaxCallObject.prototype.GetAjaxCallType = function(element)
{
	if (element == null)
		return "none";
		
	var attrib = element.getAttribute("AjaxCall");
	if (attrib != null && attrib != '')
		return attrib.toLowerCase();

	if (element.parentNode == null || element.parentNode == document.body)
		return "none";
	else
		return this.GetAjaxCallType(element.parentNode);
}

AjaxCallObject.prototype.GetAjaxScopeID = function(element)
{
	if (element == null)
		return null;
		
	var attrib = element.getAttribute("AjaxLocalScope");
	if ( attrib != null && attrib.toLowerCase() == "true" )
		return element.getAttribute("id")

	if (element.parentNode == null || element.parentNode == document.body)
		return null;
	else
		return this.GetAjaxScopeID(element.parentNode);
}

AjaxCallObject.prototype.ExcludeFromPost = function(element, scopeID, flags)
{
	var excludeAttr = element.getAttribute("ExcludeFromPost");
	if (excludeAttr != null && excludeAttr.toLowerCase() == "true")
		return true;

	var name = element.name;

	if (element.type == "hidden")
	{
		if ( name == "__MAGICAJAX_CONFIG" )
			return false;

		if ( excfAllHidden == (flags & excfAllHidden) )
			return true;

		if (name == "__VIEWSTATE")
		{
			return ( excfViewState == (flags & excfViewState) );
		}
		
		var fprintConst = "__CONTROL_FINGERPRINTS_";
		if (name.indexOf(fprintConst) == 0)
		{
			if ( excfFingerprints == (flags & excfFingerprints) )
				return true;
			
			if (scopeID != null)
			{
				fprintElem = document.getElementById(name.substr(fprintConst.length));
				if ( ! this.IsInAjaxScope(fprintElem, scopeID) )
					return true;
			}
		}
		else
		{
			return ( excfUserHidden == (flags & excfUserHidden) );
		}
	}
	else
	{
		if ( excfFormElements == (flags & excfFormElements) )
			return true;

		return ( scopeID != null && !this.IsInAjaxScope(element, scopeID) )
	}	

	return false;
}

AjaxCallObject.prototype.GetExcludeFlags = function(element)
{
	if (element == null)
		return 0;

	var flags = 0;
	var flagsAttr = element.getAttribute("ExcludeFlags");
	if (flagsAttr != null)
		flags = eval(flagsAttr);
	
	if (element.parentNode == null || element.parentNode == document.body)
		return flags;
	else
		return ( flags | this.GetExcludeFlags(element.parentNode) );
}

AjaxCallObject.prototype.IsInAjaxScope = function(element, scopeID)
{
	var attrib = element.getAttribute("AjaxLocalScope");
	if ( attrib != null && attrib.toLowerCase() == "true" && element.getAttribute("id") == scopeID )
		return true;

	if (element.parentNode == null || element.parentNode == document.body)
		return false;
	else
		return this.IsInAjaxScope(element.parentNode, scopeID);
}

AjaxCallObject.prototype.GetTargetElement = function(eventTarget)
{
	var target = document.getElementById(eventTarget);
	if (target != null)
		return target;
		
	var elemUniqueID = eventTarget.split("$").join(":");
	var ids = elemUniqueID.split(":");

	// Checks the unique id and its parents until it finds a target element
	// i.e. for ajaxPanel_grid:row:field it checks
	//   ajaxPanel_grid_row_field
	//   ajaxPanel_grid_row
	//   ajaxPanel_grid
	for (var num=ids.length; num > 0; num--)
	{
		var elemID = "";
		for (var i=0; i < num; i++)
			elemID += (i==0 ? "" : "_") + ids[i];
		
		target = document.getElementById(elemID);
		if (target != null)
			break;
	}
	// If no element found, try last id (fixes .NET 1.1 calendar control bug)
	if (target == null && ids.length > 1)
		target = document.getElementById(ids[ids.length-1]);
	
	return target;
}

AjaxCallObject.prototype.AddEventListener = function(obj, eventName, fn, capture)
{
    if (typeof(capture)=="undefined") capture=false;
    if (obj.addEventListener)
	    obj.addEventListener(eventName, fn, capture);
    else
        obj.attachEvent("on"+eventName, fn);
}

AjaxCallObject.prototype.DispatchEvent = function(obj, eventName)
{
	if (obj.fireEvent)
		obj.fireEvent("on"+eventName);
	else
	{
		var evt = document.createEvent("Events")
		evt.initEvent(eventName, true, true);
		obj.dispatchEvent(evt);
	}
}

AjaxCallObject.prototype.HookAjaxCall = function(bPageIsStored, bUnloadStoredPage, bTracing, pageFormID)
{
	__IsIE = navigator.appName.indexOf("Internet Explorer") != -1;
    __IsOpera = window.opera ? true : false;
    __PageForm = document.getElementById(pageFormID);
    
    if (__PageForm == null) return;

	this.AddEventListener(__PageForm, "submit", this.OnFormSubmit);
	this.AddEventListener(__PageForm, "click", this.OnFormClick, true);

	if (typeof __doPostBack != 'undefined')
	{
		__PreviousPostBack = __doPostBack;
		__doPostBack = this.DoPostBack;
	}
	
	__bPageIsStored = bPageIsStored;
	__bUnloadStoredPage = bUnloadStoredPage;
	__bTracing = bTracing;

	if (typeof(RBS_Controls) != "undefined")
	{
		for (var i=0; i < RBS_Controls.length; i++)
			RBS_Controls_Store[i].setAttribute("ExcludeFromPost", "true");
	}

	if ( !bPageIsStored || !bUnloadStoredPage )
	{
		this.AddEventListener(window, "load", this.OnPageLoad);
		this.AddEventListener(window, "beforeunload", this.OnPageBeforeUnload);
	}

	this.AddEventListener(window, "unload", this.OnPageUnload);
}

AjaxCallObject.prototype.OnFormClick = function(e)
{
	__ClkEvent = e;
}

AjaxCallObject.prototype.OnFormSubmit = function(e)
{
	if (__doingSubmit)
	{
		__doingSubmit = false;
	    if (e.preventDefault)
	        e.preventDefault();
	    e.returnValue=false;
		return false;
	}

    if (typeof(Page_ClientValidate)=="function")
    {
        if (window.event && !__IsOpera)
        {
            if (window.event.returnValue == false)
                return;
        }
        else if (e.getPreventDefault && e.getPreventDefault() == true)
            return;
    }
    
	// Empty the cached html of RenderedByScript controls
	if (typeof(RBS_Controls) != "undefined")
	{
		for (var i=0; i < RBS_Controls.length; i++)
			RBS_Controls_Store[i].value = "";
	}

	var target;
	if ("activeElement"	in document)
	{
		// Internet Explorer and Opera
		target = document.activeElement;
	}
	else
	{
		// Firefox
		target = e ? e.explicitOriginalTarget : null;
	}

    if (target == null || target.name == null || target.name == "")
        return true;

	var cbType = AJAXCbo.GetAjaxCallType(target);
	if (cbType != "none")
	{
		__doingSubmit = true;
		AJAXCbo.DispatchEvent(__PageForm, "submit");
		__doingSubmit = false;

		var theData = "";
		//check if target is an input element of type 'image'
		if (target != null && target.type == "image")
		{
			if (e.offsetX)
			{
				// IE
				theData = target.name + ".x=" + (e.offsetX - target.offsetLeft) + "&" + target.name + ".y=" + (e.offsetY - target.offsetTop);
			}
			else
			{
				// Firefox
				theData = target.name + ".x=" + (__ClkEvent.pageX - target.offsetLeft) + "&" + target.name + ".y=" + (__ClkEvent.pageY - target.offsetTop);
			}
		}

	    if (AJAXCbo.DoAjaxCall(target.name, "", cbType, AJAXCbo.GetAjaxScopeID(target), theData))
	    {
	        if (e.preventDefault)
	            e.preventDefault();
	        e.returnValue = false;
			return false;
	    }
	    else
			return true;
	}
	else
	{
		AJAXCbo.ClearTracingWindows();
		return true;
	}
}

// Replaces normal __doPostBack
AjaxCallObject.prototype.DoPostBack = function(eventTarget, eventArgument)
{
    if (typeof(WebForm_OnSubmit)=="function")
    {
        if (__PageForm.onsubmit && (__PageForm.onsubmit() == false))
            return;
    }

	// Empty the cached html of RenderedByScript controls
	if (typeof(RBS_Controls) != "undefined")
	{
		for (var i=0; i < RBS_Controls.length; i++)
			RBS_Controls_Store[i].value = "";
	}
	
	var target = AJAXCbo.GetTargetElement(eventTarget);
	var cbType = AJAXCbo.GetAjaxCallType(target);
	if (cbType != "none")
	{
		AJAXCbo.DoAjaxCall(eventTarget, eventArgument, cbType, AJAXCbo.GetAjaxScopeID(target));
		
		if (target.tagName == "INPUT" && (target.type == "submit" || target.type == "image"))
		{
			if (window.event)
			{
				window.event.returnValue = false;
			}
			else if (__ClkEvent)
			{
				if (__ClkEvent.preventDefault)
					__ClkEvent.preventDefault();
			}
		}
	}
	else
	{
		if (__PreviousPostBack != null)
		{
			__PreviousPostBack(eventTarget, eventArgument);
		}
	}
}

AjaxCallObject.prototype.OnPageLoad = function()
{
	// Restore the html of RenderedByScript controls
	if (typeof(RBS_Controls) != "undefined")
	{
		for (var i=0; i < RBS_Controls.length; i++)
		{
			var html = RBS_Controls_Store[i].value;
			if (html != "")
			{
				RBS_Controls[i].innerHTML = html.substring(5, html.length);
				RBS_Controls_Store[i].value = "";
			}
		}
	}
}

AjaxCallObject.prototype.OnPageBeforeUnload = function()
{
	// Save the html of RenderedByScript controls, so that it can be restored for the
	// browser's "Back Button"
	if (typeof(RBS_Controls) != "undefined")
	{
		for (var i=0; i < RBS_Controls.length; i++)
			RBS_Controls_Store[i].value = "HTML:" + RBS_Controls[i].innerHTML;
	}
}

AjaxCallObject.prototype.OnPageUnload = function()
{
	AJAXCbo.ClearTracingWindows();

	if ( !__bPageIsStored || !__bUnloadStoredPage )
		return;
	
	if (__PageForm["__AJAX_PAGEKEY"] == null)
		return;

	var thePage = __PageForm.action;
	var index = thePage.indexOf("?");
	if (index != -1)
		thePage = thePage.substring(0, index);

	thePage = thePage + "?__AJAX_PAGEUNLOAD=" + encodeURIComponent(__PageForm["__AJAX_PAGEKEY"].value);

	var oThis = AJAXCbo;
	__AJAXCboList.push(oThis);
	AJAXCbo = new AjaxCallObject();

	if( oThis.XmlHttp )
	{
		oThis.XmlHttp.open('GET', thePage, true);
		oThis.XmlHttp.onreadystatechange = function(){ };
		oThis.XmlHttp.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
		oThis.XmlHttp.send(null);
	}
}
 
AjaxCallObject.prototype.DoAjaxCall = function(eventTarget, eventArgument, ajaxCallType, ajaxScopeID, additionalData)
{
	var target = this.GetTargetElement(eventTarget);

	//defaults
	if (!ajaxCallType) ajaxCallType = "async";
	if (typeof(ajaxScopeID) == "undefined")
		ajaxScopeID = this.GetAjaxScopeID( target );

	var theData = '';
	var theform = __PageForm;
	var thePage = theform.action;
	var eName = '';

	theData  = '__EVENTTARGET='  + this.EncodePostData(eventTarget.split("$").join(":")) + '&';
	theData += '__EVENTARGUMENT=' + this.EncodePostData(eventArgument) + '&';
	theData += '__AJAXCALL=true&';
  
	if (ajaxScopeID != null)
		theData += '__AJAXSCOPE=' + ajaxScopeID + '&';

	if (typeof(additionalData) != "undefined" && additionalData != "")
		theData += additionalData + "&";	

	var excludeFlags = this.GetExcludeFlags( target );

	var elemCount = theform.elements.length;
	for( var i=0; i<elemCount; i++ )
	{
		curElem = theform.elements[i];
		eName = curElem.name;
		if( eName && eName != '' && curElem.tagName != "EMBED")
		{
			if( eName == '__EVENTTARGET' || eName == '__EVENTARGUMENT' )
			{
				// Do Nothing
			}
			else if ( ! this.ExcludeFromPost(curElem, ajaxScopeID, excludeFlags) )
			{
				if ( __bPageIsStored && eName == '__VIEWSTATE' )
					continue;

				var type = curElem.type;
				var val = curElem.value;

				if ( type == "submit" || type == "button" )
					continue;

				val = this.EncodePostData(val);

				if ( type == "select-multiple" || type == "select-one" )
				{
					var selectLength = curElem.options.length;
					var optNameStr = this.EncodePostData(eName);
					for (var j=0; j < selectLength; j++)
						if (curElem.options[j].selected)
							theData = theData + optNameStr + '=' + this.EncodePostData(curElem.options[j].value) + '&';
				}
				else if ( (type != "checkbox" && type != "radio") || curElem.checked )
				{
					theData = theData + this.EncodePostData(eName) + '=' + val + '&';
				}
			}
		}
	}
  
	if (theData.substr(theData.length-1) == "&")
		theData = theData.substr(0, theData.length-1);
		
	if( this.XmlHttp )
	{		
		if (waitElement)
		{
			waitElement.style.visibility = 'visible';
			MoveWaitElement();
		}

		var oThis = this;
		__AJAXCboList.push(oThis);
		AJAXCbo = new AjaxCallObject();
		
		if (__bTracing)
		{