//判斷fck的內容是否為空 
var oEditor = FCKeditorAPI.GetInstance('content'); //這里的content是FCK的ID值 
if(GetLength("content")<=0) { 
alert('內容不能為空!'); 
oEditor.Focus(); 
return false; 
} 


function GetLength(str){ 
var oEditor = FCKeditorAPI.GetInstance(str) ; 
var checkContent= oEditor.EditorDocument ; 
var contentLength ; 
if ( document.all ){ 
contentLength= checkContent.body.innerText.trim().length ; 
} 
else{ 
var r = checkContent.createRange() ; 
r.selectNodeContents( checkContent.body ) ; 
contentLength= r.toString().trim().length ; 
} 
return contentLength; 
} 

//去掉字符串的空格 
String.prototype.trim = function() 
{ 
return this.replace(/(^[/s]*)|([/s]*$)/g, ""); 
}