下面有一个脚本，它可以动态添加行。在 addRow 函数中，我们有以下代码alert(newcell.childNodes[0].type);捕获子节点类型。它仅将第一列显示为复选框，但其余所有显示为未定义。另外，对于第四列，我们有多个子节点，即一个按钮，其中还有一张表？那么如何知道它们的类型呢？
<html>
<head>
<script language="javascript">
function addRow(tableID) {
var table = document.getElementById(tableID);
var rowCount = table.rows.length;
var row = table.insertRow(rowCount);
var colCount = table.rows[0].cells.length;
for(var i=0; i<colCount; i++) {
var newcell = row.insertCell(i);
newcell.innerHTML = table.rows[1].cells[i].innerHTML;
newcell.innerHTML = newcell.innerHTML;
alert(newcell.childNodes[0].type);
}
}
function addSubRow2(subtbl){
var table = document.getElementById(subtbl);
var rowCount = table.rows.length;
var a=document.getElementById(subtbl).insertRow(rowCount);
var b=a.insertCell(0);
var c=a.insertCell(1);
b.innerHTML="TEST";
c.innerHTML="<p class=error id='slaveIDError'>";
/* var dropdown="<SELECT class=\"select\" name=\"country\">\n" +
"<OPTION value=\"1\">Serial 1<\/OPTION>\n" +
"<OPTION value=\"2\">Serial 2<\/OPTION>\n" +
"<OPTION value=\"3\">Serial 3<\/OPTION>\n" +
"<OPTION value=\"4\">Serial 4<\/OPTION>" +
"<OPTION value=\"5\">Serial 5<\/OPTION>" +
"<\/SELECT>";
*/
//cell.innerHTML += "<br\/ >" + dropdown;
}
function deleteRow(tableID) {
try {
var table = document.getElementById(tableID);
var rowCount = table.rows.length;
for(var i=0; i<rowCount; i++) {
var row = table.rows[i];
var chkbox = row.cells[0].childNodes[0];
if(null != chkbox && true == chkbox.checked) {
if(rowCount <= 1) {
alert("Cannot delete all the rows.");
break;
}
table.deleteRow(i);
rowCount--;
i--;
}
}
var table = document.getElementById(tableID);
for (var i = 0, row; row = table.rows[i]; i++) {
row.id="row"+i;
//iterate through rows
//rows would be accessed using the "row" variable assigned in the for loop
for (var j = 0, col; col = row.cells[j]; j++) {
//iterate through columns
//columns would be accessed using the "col" variable assigned in the for loop
//alert("J : "+j);
col.id="col"+i;
if(j==0)
{
}
else if(j==1)
{
}
}
}
}catch(e) {
alert(e);
}
}
</script>
</head>
<body>
Begin Location : <select class='select' id="beginLocation" name="beginLocation">
<option value="1">Loc 1</option>
<option value="2">Loc 2</option>
<option value="3">Loc 3</option>
<option value="4">Loc 4</option>
<option value="5">Loc 5</option>
</select>
<p type="text" class=error id='beginLocation_Error'>
<br\>
<input type="button" value="Add Row" onclick="addRow('dataTable')" />
<input type="button" value="Delete Row" onclick="deleteRow('dataTable')" />
<table id="dataTable" width="350px" border="1">
<tr>
<th></th>
<th>Client</th>
<th>Location</th>
<th>Serial</th>
</tr>
<tr>
<td id="col_0_0"><input type="checkbox" name="chk"/></td>
<td id="col_0_1">
<select class='select' id="client1" name="client1">
<option value="1">Client 1</option>
<option value="2">Client 2</option>
<option value="3">Client 3</option>
<option value="4">Client 4</option>
<option value="5">Client 5</option>
</select><p type="text" class=error id='client_0_Error'>
</td>
<td id="col_0_1">
<select class='select' id="location1" name="location1">
<option value="1">Loc 1</option>
<option value="2">Loc 2</option>
<option value="3">Loc 3</option>
<option value="4">Loc 4</option>
<option value="5">Loc 5</option>
</select>
<p type="text" class=error id='beginLocation_Error'>
</td>
<td id="col_0_3">
<input type="button" value="Add Serial" onclick="addSubRow2('sub0');" />
<br\>
<table id="sub0">
<tr>
<td>
<select class='select' id="serial_0_1" name="serial_0_1">
<option value="1">Serial 1</option>
<option value="2">Serial 2</option>
<option value="3">Serial 3</option>
<option value="4">Serial 4</option>
<option value="5">Serial 5</option>
</select>
</td>
<td>
<input type="text" id="txt_0_1" name="txt_0_1">
</td>
<td>
<input type="button" value="Remove" onclick="removeSubRow2(this.parentNode);" />
</td>
</tr>
<tr>
<td>
<p class=error id="selecterror_0_1">
</td>
<td>
<p class=error id="inputerror_0_1">
</td>
<td>
</td>
</tr>
</table>
</td>
</tr>
</table>
</body>
</html>
更新行和列 ID 的代码
var rows = table.querySelectorAll('[id^=row]');
for (var i = 0, row; row = table.rows[i]; i++) {
row.id="row"+i;
row.name="row"+i;
var rowName = "row"+i;
for (var j = 0, col; col = row.cells[j]; j++) {
col.id="col_"+i+"_"+j;
col.name="col_"+i+"_"+j;
if(j==3)
{
alert(col.childNodes[0].getElementsByTagName('button')[0]);
}
}
最佳答案
childNodes 属性包含文本节点，因此通过执行 newcell.childNodes[0] 您将引用 select 元素之前的空白.
相反，你应该这样做:
newcell.childNodes[0].getElementsByTagName('select')[0]
或
newcell.childNodes[0].getElementsByTagName('input')[0]
关于Javascript 表子项未显示为未定义？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/12488371/