Post a Javascript code commonly used in Mozilla_Basic knowledge
The unique readers and writers in Mozilla (defineGetter, defineSetter) can add prototypes to Elements, Events, etc., so that the methods used in IE can also be applied in Mozilla. Some commonly used codes are posted below
For example
obj.insertAdjacentHTML, currentStyle, obj.attachEvent, obj.detachEvent, etc.
Copyright belongs to Erik Arvidsson, webfx
extendEventObject();
emulateAttachEvent();
emulateEventHandlers(["click", "dblclick", "mouseover", "mouseout",
"mousedown", "mouseup", "mousemove",
"keydown", "keypress", "keyup"]);
emulateCurrentStyle();
/*emulateDocumentAll();
emulateElement()
*/
// It is better to use a constant for event.button
Event.LEFT = 0;
Event.MIDDLE = 1;
Event.RIGHT = 2;
}
else {
Event = {};
// IE is returning wrong button number
Event.LEFT = 1;
Event.MIDDLE = 4;
Event.RIGHT = 2;
}
/*
* Extends the event object with srcElement, cancelBubble, returnValue,
* fromElement and toElement
*/
function extendEventObject() {
Event.prototype.__defineSetter__("returnValue", function (b) {
if (!b) this.preventDefault();
return b;
});
Event.prototype.__defineSetter__("cancelBubble", function (b) {
if (b) this.stopPropagation();
return b;
});
Event.prototype.__defineGetter__("srcElement", function () {
var node = this.target;
while (node.nodeType != 1) node = node.parentNode;
return node;
});
Event.prototype.__defineGetter__("fromElement", function () {
var node;
if (this.type == "mouseover")
node = this.relatedTarget;
else if (this.type == "mouseout")
node = this.target;
if (!node) return;
while (node.nodeType != 1) node = node.parentNode;
return node;
});
Event.prototype.__defineGetter__("toElement", function () {
var node;
if (this.type == "mouseout")
node = this.relatedTarget;
else if (this.type == "mouseover")
node = this.target;
if (!node) return;
while (node.nodeType != 1) node = node.parentNode;
return node;
});
Event.prototype.__defineGetter__("offsetX", function () {
return this.layerX;
});
Event.prototype.__defineGetter__("offsetY", function () {
return this.layerY;
});
}
/*
* Emulates element.attachEvent as well as detachEvent
*/
function emulateAttachEvent() {
HTMLDocument.prototype.attachEvent =
HTMLElement.prototype.attachEvent = function (sType, fHandler) {
var shortTypeName = sType.replace(/on/, "");
fHandler._ieEmuEventHandler = function (e) {
window.event = e;
return fHandler();
};
this.addEventListener(shortTypeName, fHandler._ieEmuEventHandler, false);
};
HTMLDocument.prototype.detachEvent =
HTMLElement.prototype.detachEvent = function (sType, fHandler) {
var shortTypeName = sType.replace(/on/, "");
if (typeof fHandler._ieEmuEventHandler == "function")
this.removeEventListener(shortTypeName, fHandler._ieEmuEventHandler, false);
else
this.removeEventListener(shortTypeName, fHandler, true);
};
}
/*
* This function binds the event object passed along in an
* event to window.event
*/
function emulateEventHandlers(eventNames) {
for (var i = 0; i < eventNames.length; i ) {
document.addEventListener(eventNames[i], function (e) {
window.event = e;
}, true); // using capture
}
}
/*
* Simple emulation of document.all
* this one is far from complete. Be cautious
*/
function emulateAllModel() {
var allGetter = function () {
var a = this.getElementsByTagName("*");
var node = this;
a.tags = function (sTagName) {
return node.getElementsByTagName(sTagName);
};
return a;
};
HTMLDocument.prototype.__defineGetter__("all", allGetter);
HTMLElement.prototype.__defineGetter__("all", allGetter);
}
function extendElementModel() {
HTMLElement.prototype.__defineGetter__("parentElement", function () {
if (this.parentNode == this.ownerDocument) return null;
return this.parentNode;
});
HTMLElement.prototype.__defineGetter__("children", function () {
var tmp = [];
var j = 0;
var n;
for (var i = 0; i < this.childNodes.length; i ) {
n = this.childNodes[i];
if (n.nodeType == 1) {
tmp[j ] = n;
if (n.name) { // named children
if (!tmp[n.name])
tmp[n.name] = [];
tmp[n.name][tmp[n.name].length] = n;
}
if (n.id) // child with id
tmp[n.id] = n
}
}
return tmp;
});
HTMLElement.prototype.contains = function (oEl) {
if (oEl == this) return true;
if (oEl == null) return false;
return this.contains(oEl.parentNode);
};
}
function emulateCurrentStyle() {
HTMLElement.prototype.__defineGetter__("currentStyle", function () {
return this.ownerDocument.defaultView.getComputedStyle(this, null);
/*
var cs = {};
var el = this;
for (var i = 0; i < properties.length; i ) {
cs.__defineGetter__(properties[i], encapsulateObjects(el, properties[i]));
}
return cs;
*/
});
}
function emulateHTMLModel() {
// This function is used to generate a html string for the text properties/methods
// It replaces 'n' with "
as well as fixes consecutive white spaces
// It also repalaces some special characters
function convertTextToHTML(s) {
s = s.replace(/&/g, "&").replace(//g, ">").replace(/n/g, "
");
while (/ss/.test(s))
s = s.replace(/ss/, " ");
return s.replace(/s/g, " ");
}
HTMLElement.prototype.insertAdjacentHTML = function (sWhere, sHTML) {
var df; // : DocumentFragment
var r = this.ownerDocument.createRange();
switch (String(sWhere).toLowerCase()) {
case "beforebegin":
r.setStartBefore(this);
df = r.createContextualFragment(sHTML);
this.parentNode.insertBefore(df, this);
break;
case "afterbegin":
r.selectNodeContents(this);
r.collapse(true);
df = r.createContextualFragment(sHTML);
this.insertBefore(df, this.firstChild);
break;
case "beforeend":
r.selectNodeContents(this);
r.collapse(false);
df = r.createContextualFragment(sHTML);
this.appendChild(df);
break;
case "afterend":
r.setStartAfter(this);
df = r.createContextualFragment(sHTML);
this.parentNode.insertBefore(df, this.nextSibling);
break;
}
};
HTMLElement.prototype.__defineSetter__("outerHTML", function (sHTML) {
var r = this.ownerDocument.createRange();
r.setStartBefore(this);
var df = r.createContextualFragment(sHTML);
this.parentNode.replaceChild(df, this);
return sHTML;
});
HTMLElement.prototype.__defineGetter__("canHaveChildren", function () {
switch (this.tagName) {
case "AREA":
case "BASE":
case "BASEFONT":
case "COL":
case "FRAME":
case "HR":
case "IMG":
case "BR":
case "INPUT":
case "ISINDEX":
case "LINK":
case "META":
case "PARAM":
return false;
}
return true;
});
HTMLElement.prototype.__defineGetter__("outerHTML", function () {
var attr, attrs = this.attributes;
var str = "<" this.tagName;
for (var i = 0; i < attrs.length; i ) {
attr = attrs[i];
if (attr.specified)
str = " " attr.name '="' attr.value '"';
}
if (!this.canHaveChildren)
return str ">";
return str ">" this.innerHTML "" this.tagName ">";
});
HTMLElement.prototype.__defineSetter__("innerText", function (sText) {
this.innerHTML = convertTextToHTML(sText);
return sText;
});
var tmpGet;
HTMLElement.prototype.__defineGetter__("innerText", tmpGet = function () {
var r = this.ownerDocument.createRange();
r.selectNodeContents(this);
return r.toString();
});
HTMLElement.prototype.__defineSetter__("outerText", function (sText) {
this.outerHTML = convertTextToHTML(sText);
return sText;
});
HTMLElement.prototype.__defineGetter__("outerText", tmpGet);
HTMLElement.prototype.insertAdjacentText = function (sWhere, sText) {
this.insertAdjacentHTML(sWhere, convertTextToHTML(sText));
};
}

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