Question

我曾经使用如下代码验证复选框表单：

<div>
  <form action="survey.php" method="post" name="survey"> 
  <span class="form"><input type="checkbox" name="event1" onClick="return countMarketing()">Event1</span>
  <span class"form"><input type="checkbox" name="event2" onClick="return countMarketing()">Event2</span>
  <span class"form"><input type="checkbox" name="event3" onClick="return countMarketing()">Event2</span>
  <!-- other forms -->
  </form>
</div>

这样的javascript验证（限制复选框的数量）：

function countMarketing() {

        var NewCountMarketing = 0

        if (document.survey.event1.checked)
        {NewCountMarketing = NewCountMarketing + 1}

        if (document.survey.event2.checked)
        {NewCountMarketing = NewCountMarketing + 1}

        if (document.survey.event3.checked)
        {NewCountMarketing = NewCountMarketing + 1}
        if (NewCountMarketing == 3)
        {
            alert('Please choose only two')
            document.survey; return false;
        }
    }

这样的验证有效。但是现在，说我使用php来提交，如何在JS中检查表单的名称是否是这样的：

 <input type="checkbox" name="events[]" id="event1" onClick="return countMarketing()">Event1

我试图将JS改为：

if (document.survey.events[].checked)
    {code here}

if (document.survey.getElementByName('events[]').checked)
    {code here}

if (document.survey.getElementById('event1').checked)
    {code here}

但它不起作用..任何人都可以对此有所了解吗？非常感谢你:)）

Answer 1

如果你实际上在使用jQuery，你可以这样做：

在使用此功能之前，请确保在文档中包含jQuery。在尝试运行该函数之前已加载文档。

function countMarketing() {

  if( $('input[name="events[]"]').filter(':checked').length > 2 ) {
    alert('Please choose only two');
  }

}

Answer 2

首先删除inline events declaration并将其移至external Javascript file或script block

您始终可以使用bracket Notation来访问此类属性

document.survey["events[]"]

<强>代码

    var elems = document.survey,
    checkboxNames = ["event1[]", "event2[]", "event3[]"];

for (var i = 0; i < checkboxNames.length; i++) {
    bindClick(elems[checkboxNames[i]]);
}

function bindClick(elem) {
    elem.addEventListener('click', countMarketing);
}

function countMarketing() {

    var NewCountMarketing = 0
    var latest;
    for (var i = 0; i < checkboxNames.length; i++) {
        if (elems[checkboxNames[i]].checked) {
            latest = elems[checkboxNames[i]];
            NewCountMarketing++;
        }
    }

    if (NewCountMarketing == 3) {
        latest.checked = false;               
        alert('Please choose only two')
        document.survey;
        return false;
    }
}

<强> Check Fiddle

验证具有数组作为名称参数的复选框

2 个答案: