如何通過使用純 JavaScript 選中復選框來顯示表格？

Question

當復選框被選中但它不起作用時，我需要顯示一個表格。 您可以在下面找到我的腳本、復選框和表格

    <script>
    function checked() {
        var checkBox = document.getElementById("check");
        var concession = document.getElementById("hidden");
        if (checkBox.checked == true){
            concession.style.display = "block";
        } else {
            concession.style.display = "none";
        }
    }
</script>

<input type = "checkbox" name = "discount" id = "check" onclick = "checked()">

<table id = "hidden" class = "center" style = "display:none">
        <tr>
            <th>102-2 Taxable income is reduced by 400AZN</th>
            <th></th>
            <th><input type = "radio" name = "400"></th>
        </tr>
        <tr>
            <th>102-3 Taxable income is reduced by 200AZN</th>
            <th></th>
            <th><input type = "radio" name = "200"></th>
        </tr>
        <tr>
            <th>102-4 Taxable income is reduced by 100AZN</th>
            <th></th>
            <th><input type = "radio" name = "100"></th>
        </tr>
        <tr>
            <th>102-5 Taxable income is reduced by 50AZN</th>
            <th></th>
            <th><input type = "radio" name = 50"></th>
        </tr>
    </table>

我該如何解決這個問題？

Answer 1

當您使用像onclick這樣的內聯處理程序時，您需要分配一個函數，所以onclick="checked"是正確的方法

作為旁注，應該首選通過addEventListener()分配事件

<input type="checkbox" name="discount" id="check">
<table id="hidden" class="center" style="display:none">
  ...
</table>

<script>
var concession = document.getElementById("hidden");
document.getElementById("check").addEventListener('click', function() {        
    concession.style.display = (this.checked)? "block" : "none";
});
</script>

---

最后，值得注意的是，JS 根本不是必需的，因為您只能將 CSS 用於具有給定標記的此類任務

#check + table { display: none }
#check:checked + table { display: block }

Answer 2

也許checked()被限制了，改變你的函數名：

 function changed() { var checked = document.getElementById("check").checked; var concession = document.getElementById("hidden"); if (checked) { concession.style.display = "block"; } else { concession.style.display = "none"; } }

 <input type="checkbox" name="discount" id="check" onChange="changed()"> <table id="hidden" class="center" style="display:none"> <tr> <th>102-2 Taxable income is reduced by 400AZN</th> <th></th> <th><input type="radio" name="400"></th> </tr> <tr> <th>102-3 Taxable income is reduced by 200AZN</th> <th></th> <th><input type="radio" name="200"></th> </tr> <tr> <th>102-4 Taxable income is reduced by 100AZN</th> <th></th> <th><input type="radio" name="100"></th> </tr> <tr> <th>102-5 Taxable income is reduced by 50AZN</th> <th></th> <th> <input type="radio" name="50"></th> </tr> </table>

Answer 3

您遇到此問題，因為checked是保留名稱。 嘗試將函數名稱重命名為OnCheckboxClicked其他名稱以解決此問題。

演示：

 function OnCheckboxClicked() { var checkBox = document.getElementById("check"); var concession = document.getElementById("hidden"); if (checkBox.checked == true) { concession.style.display = "block"; } else { concession.style.display = "none"; } }

 <input type="checkbox" name="discount" id="check" onclick="OnCheckboxClicked()"> <table id="hidden" class="center" style="display:none"> <tr> <th>102-2 Taxable income is reduced by 400AZN</th> <th></th> <th><input type="radio" name="400"></th> </tr> <tr> <th>102-3 Taxable income is reduced by 200AZN</th> <th></th> <th><input type="radio" name="200"></th> </tr> <tr> <th>102-4 Taxable income is reduced by 100AZN</th> <th></th> <th><input type="radio" name="100"></th> </tr> <tr> <th>102-5 Taxable income is reduced by 50AZN</th> <th></th> <th> <input type="radio" name=5 0 "></th> </tr> </table>

Answer 4

您必須向復選框添加一個事件偵聽器：

var checkbox = document.querySelector("#check");

checkbox.addEventListener( 'change', function() {
var concession = document.getElementById("hidden");
    if(this.checked) {
         concession.style.display='block';
    } else {
      concession.style.display='none';
    }
});