JavaScript 表格指定列，根据相同值跨行

function mergeTableRows(tableName,colIdx){

    tableObj=document.getElementById(tableName);
    var lastTdText=null;
    var rowLen=tableObj.rows.length;
    for(var i=rowLen-1;i>=1;i--){
        var currText=tableObj.rows[i].cells[colIdx].innerHTML;
        if(lastTdText==null){
            sameCount=1;
        }else if(lastTdText!=currText){
            if(sameCount>1){
                tableObj.rows[i+1].cells[colIdx].rowSpan=sameCount;
            }

            sameCount=1;
        }else if(lastTdText==currText){
            tableObj.rows[i+1].deleteCell(colIdx);
            sameCount++;
        }

        lastTdText=currText;
    }

    if(sameCount>1){
        tableObj.rows[1].cells[colIdx].rowSpan=sameCount;
    }

    //强制表格重新绘制
    var borderWidth=tableObj.border;
    tableObj.border=1;
    tableObj.border=borderWidth;
}