ExtJs4grid合并行

/*
*合并行
*grid被格式化的表格
*cols要合并的列，数组类型，如[1,2] 合并第1列和第2列
*/
var mergeCells = function(grid,cols){  
                var arrayTr=document.getElementById(grid.getId()+"-body").getElementsByTagName(‘tbody‘)[0].getElementsByTagName(‘tr‘);
                
                var trCount = arrayTr.length;  
                var arrayTd;  
                var td;  
                var merge = function(rowspanObj,removeObjs){ 
                    if(rowspanObj.rowspan != 1){  
                        arrayTd =arrayTr[rowspanObj.tr].getElementsByTagName("td"); 
                        td=arrayTd[rowspanObj.td-1];  
                        td.rowSpan=rowspanObj.rowspan;  
                        td.vAlign="middle";               
                        Ext.each(removeObjs,function(obj){ 
                            arrayTd =arrayTr[obj.tr].getElementsByTagName("td");  
                            arrayTd[obj.td-1].style.display=‘none‘;                           
                        });  
                    }     
                };    
                var rowspanObj = {};        
                var removeObjs = []; 
                var col;  
                Ext.each(cols,function(colIndex){  
                    var rowspan = 1;  
                    var divHtml = null;          
                    for(var i=0;i<trCount;i++){   
                    arrayTd = arrayTr[i].getElementsByTagName("td");  
                        var cold=0;  
     
                        col=colIndex+cold;  
                        if(!divHtml){  
                            divHtml = arrayTd[col-1].innerHTML;  
                            rowspanObj = {tr:i,td:col,rowspan:rowspan}
                        }else{  
                            var cellText = arrayTd[col-1].innerHTML;  
                            var addf=function(){   
                                rowspanObj["rowspan"] = rowspanObj["rowspan"]+1;  
                                removeObjs.push({tr:i,td:col});  
                            if(i==trCount-1)  
                                    merge(rowspanObj,removeObjs);  
                            };  
                            var mergef=function(){  
                                merge(rowspanObj,removeObjs);  
                                divHtml = cellText;  
                                rowspanObj = {tr:i,td:col,rowspan:rowspan}  
                                removeObjs = [];  
                            };  
                            if(cellText == divHtml){  
                                if(colIndex!=cols[0]){   
                                    var leftDisplay=arrayTd[col-2].style.display;   
                                    if(leftDisplay==‘none‘)  
                                        addf();   
                                    else  
                                        mergef();                             
                                }else  
                                    addf();                                           
                            }else  
                                mergef();             
                        }  
                    }  
                });   
            };

        //调用方法合并行
        grid.getStore().on(‘load‘,function(){  
            //调用方法合并相同行数据
            mergeCells(grid,[1,2]);  
         });