//将url里面的内容复制到系统剪贴板
function copy(url){
	if(window.clipboardData){
		window.clipboardData.clearData(); 
		window.clipboardData.setData("Text", url);
	} else if(navigator.userAgent.indexOf("Opera") != -1) { 
	    window.location = txt;
    } else if (window.netscape) { 
	    try { 
	   		netscape.security.PrivilegeManager.enablePrivilege("UniversalXPConnect"); 
    	} catch (e) { 
	    	alert("您的firefox安全限制限制您进行剪贴板操作，请打开’about:config’将signed.applets.codebase_principal_support’设置为true’之后重试"); 
	    	return false; 
	    } 
	    var clip = Components.classes["@mozilla.org/widget/clipboard;1"].createInstance(Components.interfaces.nsIClipboard); 
	    if (!clip){ 
	    	return;
	    } 
	    var trans = Components.classes["@mozilla.org/widget/transferable;1"].createInstance(Components.interfaces.nsITransferable); 
	    if (!trans){ 
	    	return; 
	    }
	    trans.addDataFlavor("text/unicode"); 
	    var str = new Object(); 
	    var len = new Object(); 
	    var str = Components.classes["@mozilla.org/supports-string;1"].createInstance(Components.interfaces.nsISupportsString); 
	    var copytext = txt; 
	    str.data = copytext; 
	    trans.setTransferData("text/unicode", str,copytext.length*2); 
	    var clipid = Components.interfaces.nsIClipboard; 
	    if (!clip){
		    return false;
	    } 
	    clip.setData(trans,null,clipid.kGlobalClipboard); 
    }
}