使用javascript在html中动态添加/删除行

Adding/Removing row dynamically in html using javascript

本文关键字:添加 删除行 动态 javascript html 使用      更新时间:2023-09-26

我有这个特殊的片段..

newcell.innerHTML = table.rows[0].cells[i].innerHTML;
//alert(newcell.childNodes);
switch(newcell.childNodes[0].type) {
case "text":
    newcell.childNodes[0].value = "";
    break;
case "checkbox":
    newcell.childNodes[0].checked = false;
    break;
case "select-one":
    newcell.childNodes[0].selectedIndex = 0;
    break;
case "number":
    newcell.childNodes[0].value = '';
    break;
}

上面的开关使新添加的行从复制的行重置值。

文本和数字重置。

但是下拉框和复选框没有

这两个需要什么命令来重置它们的值?对于下拉菜单,第一个选项和复选框是不选中任何框

编辑:这是整个代码

<script type="text/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;
            switch(newcell.childNodes[0].type) {
                case "text":
                    newcell.childNodes[0].value = "";
                    break;
                case "checkbox":
                    newcell.childNodes[0].checked = false;
                    break;
                case "select-one":
                    newcell.childNodes[0].selectedIndex = 0;
                    break;
                case "number":
                    newcell.childNodes[0].value = '';
                    break;
            }
        }
    }
    function deleteRow(tableID) {
        try {
        var table = document.getElementById(tableID);
        var rowCount = table.rows.length;
        var colCount = table.rows[0].cells.length;
        for(var i=0; i<rowCount; i++) {
            var row = table.rows[i];
            var chkbox = row.cells[colCount-1].childNodes[0];
            if(null != chkbox && true == chkbox.checked) {
                if(rowCount <= 2) {
                    alert("Cannot delete all the rows.");
                    break;
                }
                table.deleteRow(i);
                rowCount--;
                i--;
            } 
        }
        }catch(e) {
            alert(e);
        }
    }
</script>
<body>
<label><input type="checkbox" id='checkboxId'>N/A</label>   
<br>
<div id="div-table-id">
    <table id='table-id' border="1">
        <tr>
            <th>Subject</th>
            <th>Section Code</th>
            <th>Room</th>
            <th>Days</th>
            <th>Start Time</th>
            <th>End Time</th>
            <th>Hours Per Week</th>
            <th>No of Students (A)</th>
            <th>Course Credit w/o multiplier(B)</th>
            <th>Student Credit Units (AxB)</th>
            <th>Teaching Load Credits with Multiplier</th>
            <th>Delete?</th>
        </tr>
        <tr>
            <td>
                <select name="subject" >
                    <option value="cmsc2">CMSC2</option>
                    <option value="cmsc11" selected="selected">CMSC11</option>
                    <option value="cmsc121">CMSC121</option>
                </select>
            </td>
            <td><input type="text" id="password" value="sample"/></td>
            <td><input type="text" id="password2" value="sample"/></td>
            <td>
                <input type="checkbox" name="days" value="m" checked>M
                <input type="checkbox" name="days" value="t">T
                <input type="checkbox" name="days" value="m">W
                <input type="checkbox" name="days" value="th">Th
                <input type="checkbox" name="days" value="f">F
                <input type="checkbox" name="days" value="s">S
            </td>
            <td><input type="time" name="start_time"></td>
            <td><input type="time" name="end_time"></td>
            <td><input type="number" name="hpw"></td>   
            <td><input type="number" name="nos"></td>
            <td><input type="number" name="ccm"></td>
            <td><input type="number" name="scu"></td>
            <td><input type="number" name="tlcm"></td>
            <td><input type="checkbox" name="chk"></td>
        </tr>
    </table>
    <input type="button" value="Add Row" onclick="addRow('table-id')" />
    <input type="button" value="Delete Row" onclick="deleteRow('table-id')"/>       
    <input type="button" value="Save"/>
</div>
<script>
    document.getElementById('checkboxId').onchange = function () {
        var elems = document.getElementById('div-table-id').querySelectorAll('input,select,textarea');
        if (document.getElementById('checkboxId').checked) {
            for (var i = 0; i < elems.length; i++) {
                elems[i].disabled = true;
            }
        } else {
            for (var i = 0; i < elems.length; i++) {
                elems[i].disabled = false;
            }    
        }
    }
    document.getElementById('password2').disabled = true;
    document.getElementById('password').onblur = function(){
        if(document.getElementById('password').value != '')
            document.getElementById('password2').disabled = false;
        else{
            document.getElementById('password2').value = '';
            document.getElementById('password2').disabled = true;
        }
        document.getElementById("password2").select();
    }
    document.getElementById('password2').onblur = function (){
        if(document.getElementById('password').value == '')
            return;
        check();
    }
    function check() {
        if (document.getElementById('password2').value != document.getElementById('password').value) {
            alert('The two passwords must match.');
            document.getElementById("password").select();
            document.getElementById('password2').value = '';
        }
        else 
            alert('The two passwords matched.');
    }
</script>

好了,我知道你的问题是什么了。当您将新表格单元格的内容指定为第一行内容时,如下

newcell.innerHTML=table.rows[1].cells[i].innerHTML;

在输入/选择元素周围复制一些空白,有时这些空白会成为文本节点。因此,在第一个TD中的SELECT元素的情况下,DOM实际上看起来像这样:

  • [0] #Text node
  • [1]选择
  • [2] #Text node

这意味着当您抓取第一个子newcell.childNodes[0]时,您抓取Text节点,SELECT或CHECKBOX保持不变。我重写了你的代码,包括一个函数,将重置一个新单元格的所有子,因为这也涵盖的情况下,有人检查了更多的复选框在第一行,你用来追加一个新的行。

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;
            resetChildren( newcell );
        }
    }
function resetChildren( parentEl ){
    var len = parentEl.childNodes.length,
        i = 0,
        el;
    for(i = 0; i < len; i++){
        el = parentEl.childNodes[i];
        console.log( i, el.type, el );
        switch( el.type ){
            case "text":
                el.value = "";
                break;
            case "checkbox":
                el.removeAttribute('checked');
                break;
            case "select-one":
                el.selectedIndex = 0;
                break;
            case "number":
                el.value = '';
                break;
        }
    }
}