JS 获取fckeditor中的值

var oEditor = FCKeditorAPI.GetInstance("fckSummary");
            var oDOM = oEditor.EditorDocument;
            var iLength ;
            if(document.all){
              var resultStr=oDOM.body.innerText.replace(/[ ]/g,"");    //去掉空格
              resultStr=resultStr.replace(/[\r\n]/g,"");//去掉回车换行   
             iLength = resultStr.length;
            }else{
             var r = oDOM.createRange();
             r.selectNodeContents(oDOM.body);
             iLength = r.toString().length;
            }
            if(iLength==0){
               alert("留言内容不能为空！");
               return false;
            }
            if(iLength < 6){
               alert("留言内容不能少于6个字符！");
               return false;
            }