Javascript复制实例详解

在做项目时有一个需求，是需要复制内容到剪切板，因为有众多浏览器，所以要兼容性很重要。

1、最简单的copy，只能在IE下使用

使用clipboardData方法

2、跨浏览器的，但是Firefox无法复制

Copy text to clipboard

测试后，Firefox访问失败

3、万能的flash

不要重复造轮子了，有一个使用广泛的类库ZeroClipboard

Zero Clipboard 的实现原理

Zero Clipboard 利用 Flash 进行复制，之前有 Clipboard Copy 解决方案，其利用的是一个隐藏的 Flash。但最新的 Flash Player 10 只允许在 Flash 上进行操作才能启动剪贴板。所以 Zero Clipboard 对此进行了改进，用了一个透明的 Flash ，让其漂浮在按钮之上，这样其实点击的不是按钮而是 Flash ，也就可以使用 Flash 的复制功能了。

创建一个透明的flash

将这个flash浮在按钮上层

确定要复制的文本是什么

监听这个透明flash的鼠标点击事件

该flash被点击之后，完成剪切板处理

对于这几件事，ZeroClipboard分别提供了不同的api，来完成整个需求

如何使用 Zero Clipboard

git clone https://github.com/chenpingzhao/easycopy.git

关于ZeroClipboard.js

var ZeroClipboard = {
version: "1.0.7",
clients: {},
moviePath: "zeroclipboard.swf",
nextId: 1,
$: function(A) {
if (typeof(A) == "string") {
A = document.getElementById(A)
}
if (!A.addClass) {
A.hide = function() {
this.style.display = "none"
};
A.show = function() {
this.style.display = ""
};
A.addClass = function(B) {
this.removeClass(B);
this.className += " " + B
};
A.removeClass = function(D) {
var E = this.className.split(/s+/);
var B = -1;
for (var C = 0; C < E.length; C++) {
if (E[C] == D) {
B = C;
C = E.length
}
}
if (B > -1) {
E.splice(B, 1);
this.className = E.join(" ")
}
return this
};
A.hasClass = function(B) {
return !!this.className.match(new RegExp("\s*" + B + "\s*"))
}
}
return A
},
setMoviePath: function(A) {
this.moviePath = A
},
dispatch: function(D, B, C) {
var A = this.clients[D];
if (A) {
A.receiveEvent(B, C)
}
},
register: function(B, A) {
this.clients[B] = A
},
getDOMObjectPosition: function(C, A) {
var B = {
left: 0,
top: 0,
width: C.width ? C.width : C.offsetWidth,
height: C.height ? C.height : C.offsetHeight
};
while (C && (C != A)) {
B.left += C.offsetLeft;
B.top += C.offsetTop;
C = C.offsetParent
}
return B
},
Client: function(A) {
this.handlers = {};
this.id = ZeroClipboard.nextId++;
this.movieId = "ZeroClipboardMovie_" + this.id;
ZeroClipboard.register(this.id, this);
if (A) {
this.glue(A)
}
}
};
ZeroClipboard.Client.prototype = {
id: 0,
ready: false,
movie: null,
clipText: "",
handCursorEnabled: true,
cssEffects: true,
handlers: null,
//我们可以通过下面这个api，将flash和按钮重叠，且浮在按钮之上
glue: function(D, B, E) {
this.domElement = ZeroClipboard.$(D);
var F = 99;
if (this.domElement.style.zIndex) {
F = parseInt(this.domElement.style.zIndex, 10) + 1
}
if (typeof(B) == "string") {
B = ZeroClipboard.$(B)
} else {
if (typeof(B) == "undefined") {
B = document.getElementsByTagName("body")[0]
}
}
var C = ZeroClipboard.getDOMObjectPosition(this.domElement, B);
this.div = document.createElement("div");
var A = this.div.style;
A.position = "absolute";
A.left = "" + C.left + "px";
A.top = "" + C.top + "px";
A.width = "" + C.width + "px";
A.height = "" + C.height + "px";
A.zIndex = F;
if (typeof(E) == "object") {
for (addedStyle in E) {
A[addedStyle] = E[addedStyle]
}
}
B.appendChild(this.div);
this.div.innerHTML = this.getHTML(C.width, C.height)
},

getHTML: function(D, A) {
var C = "";
var B = "id=" + this.id + "&width=" + D + "&height=" + A;
if (navigator.userAgent.match(/MSIE/)) {
var E = location.href.match(/^https/i) ? "https://" : "http://";
C += ''
} else {
C += ''
}
return C
},
hide: function() {
if (this.div) {
this.div.style.left = "-2000px"
}
},
show: function() {
this.reposition()
},
destroy: function() {
if (this.domElement && this.div) {
this.hide();
this.div.innerHTML = "";
var A = document.getElementsByTagName("body")[0];
try {
A.removeChild(this.div)
} catch (B) {}
this.domElement = null;
this.div = null
}
},

reposition: function(C) {
if (C) {
this.domElement = ZeroClipboard.$(C);
if (!this.domElement) {
this.hide()
}
}
if (this.domElement && this.div) {
var B = ZeroClipboard.getDOMObjectPosition(this.domElement);
var A = this.div.style;
A.left = "" + B.left + "px";
A.top = "" + B.top + "px"
}
},
setText: function(A) {
this.clipText = A;
if (this.ready) {
this.movie.setText(A)
}
},
addEventListener: function(A, B) {
A = A.toString().toLowerCase().replace(/^on/, "");
if (!this.handlers[A]) {
this.handlers[A] = []
}
this.handlers[A].push(B)
},
setHandCursor: function(A) {
this.handCursorEnabled = A;
if (this.ready) {
this.movie.setHandCursor(A)
}
},




setCSSEffects: function(A) {
this.cssEffects = !! A
},

receiveEvent: function(D, E) {
D = D.toString().toLowerCase().replace(/^on/, "");
switch (D) {
case "load":
this.movie = document.getElementById(this.movieId);
if (!this.movie) {
var C = this;
setTimeout(function() {
C.receiveEvent("load", null)
}, 1);
return
}
if (!this.ready && navigator.userAgent.match(/Firefox/) && navigator.userAgent.match(/Windows/)) {
var C = this;
setTimeout(function() {
C.receiveEvent("load", null)
}, 100);
this.ready = true;
return
}
this.ready = true;
this.movie.setText(this.clipText);
this.movie.setHandCursor(this.handCursorEnabled);
break;
case "mouseover":
if (this.domElement && this.cssEffects) {
this.domElement.addClass("hover");
if (this.recoverActive) {
this.domElement.addClass("active")
}
}
break;
case "mouseout":
if (this.domElement && this.cssEffects) {
this.recoverActive = false;
if (this.domElement.hasClass("active")) {
this.domElement.removeClass("active");
this.recoverActive = true
}
this.domElement.removeClass("hover")
}
break;
case "mousedown":
if (this.domElement && this.cssEffects) {
this.domElement.addClass("active")
}
break;
case "mouseup":
if (this.domElement && this.cssEffects) {
this.domElement.removeClass("active");
this.recoverActive = false
}
break
}
if (this.handlers[D]) {
for (var B = 0, A = this.handlers[D].length; B < A; B++) {
var F = this.handlers[D][B];
if (typeof(F) == "function") {
F(this, E)
} else {
if ((typeof(F) == "object") && (F.length == 2)) {
F[0][F[1]](this, E)
} else {
if (typeof(F) == "string") {
window[F](this, E)
}
}
}
}
}
}
}; 

以上所述是小编给大家介绍的Javascript复制实例详解，希望对大家有所帮助。