 
select(document, tanchu); 
/*=select[[ 
* 
* 跨瀏覽器選中文字事件 
* @param 
* object o 響應選中事件的DOM對象，required 
* function fn(sText,target,mouseP)選中文字非空時的回調函數(shù)，required 
* |-@param 
* |-sText 選中的文字內容 
* |-target 觸發(fā)mouseup事件的元素 
* |-mouseP 觸發(fā)mouseup事件時鼠標坐標 
*/ 
function select(o, fn){ 
o.onmouseup = function(e){ 
var event = window.event || e; 
var target = event.srcElement ? event.srcElement : event.target; 
if (/input|textarea/i.test(target.tagName) && /firefox/i.test(navigator.userAgent)) { 
//Firefox在文本框內選擇文字 
var staIndex=target.selectionStart; 
var endIndex=target.selectionEnd; 
if(staIndex!=endIndex){ 
var sText=target.value.substring(staIndex,endIndex); 
fn(sText,target); 
} 
} 
else{ 
//獲取選中文字 
var sText = document.selection == undefined ? document.getSelection().toString():document.selection.createRange().text; 
if (sText != "") { 
//將參數(shù)傳入回調函數(shù)fn 
fn(sText, target); 
} 
} 
} 
} 
/*]]select=*/ 
function tanchu(txt,tar){ 
alert("文字屬于"+tar.tagName+"元素，選中內容為："+txt); 
} 

　原作者見：http://momomolice.com/wordpress/archives/420.html

附：只獲得選取的文字的代碼（不響應該事件）

復制代碼代碼如下:

 
function getSelectedText() 
{ 
if (window.getSelection) 
{ // This technique is the most likely to be standardized. 
// getSelection() returns a Selection object, which we do not document. 
return window.getSelection().toString(); 
} 
else if (document.getSelection) 
{ 
// This is an older, simpler technique that returns a string 
return document.getSelection(); 
} 
else if (document.selection) 
{ 
// This is the IE-specific technique. 
// We do not document the IE selection property or TextRange objects. 
return document.selection.createRange().text; 
} 
} 