js 合并列

function uniteTable(tb, colLength) {  
           //   检查表格是否规整  
if (!checkTable(tb)) {
return;
}
var i = 0;
var j = 0;
var k = 0;
var rowCount = tb.rows.length; //   行数  
var colCount = tb.rows[0].cells.length; //   列数  
var obj1 = null;
var obj2 = null;  
           //   为每个单元格命名  
for (i = 0; i < rowCount; i++) {
for (j = 0; j < colCount; j++) {
tb.rows[i].cells[j].id = "tb__" + i.toString() + "_" + j.toString();
}
}  
           //   逐列检查合并  
for (i = 0; i < colCount; i++) {
if(i == 1){
continue;
}
if (i == colLength) {
return;
}
obj1 = document.getElementById("tb__0_" + i.toString());
for (j = 1; j < rowCount; j++) {
obj2 = document.getElementById("tb__" + j.toString() + "_" + i.toString());
if (obj1.innerText == obj2.innerText) {
obj1.rowSpan++;
obj2.parentNode.removeChild(obj2);
} else {
obj1 = document.getElementById("tb__" + j.toString() + "_" + i.toString());
}
}
tb.style.display = "block";
/*for(k=1;k < rowCount;k++){
//alert("dfff");
tb.rows[k].style.display = "block";
}*/

}
}  
            
 /////////////////////////////////////////
 //   功能：检查表格是否规整
 //   参数：tb－－需要检查的表格ID
 //   data:   2005.11.6  
 /////////////////////////////////////////  
function checkTable(tb) {
if (tb.rows.length == 0) {
return false;
}
if (tb.rows[0].cells.length == 0) {
return false;
}
for (var i = 0; i < tb.rows.length; i++) {
if (tb.rows[0].cells.length != tb.rows[i].cells.length) {
return false;
}
}
return true;
}