如果提交了表单,但不是通过任何特定的按钮,例如

按Enter键 使用JS中的HTMLFormElement.submit()

浏览器应该如何确定多个提交按钮(如果有的话)中的哪一个作为按下的按钮呢?

这在两个层面上很重要:

调用附加到提交按钮的onclick事件处理程序 数据发送回web服务器

到目前为止,我的实验表明:

当按Enter键时,Firefox、Opera和Safari使用表单中的第一个提交按钮 当按Enter键时,IE要么使用第一个提交按钮,要么根本不使用,这取决于我还没能弄清楚的条件 所有这些浏览器都不使用JS提交

标准是怎么说的?

如果有帮助的话,下面是我的测试代码(PHP只与我的测试方法相关,与我的问题本身无关)

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
                      "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Test</title>
</head>

<body>

<h1>Get</h1>
<dl>
<?php foreach ($_GET as $k => $v) echo "<dt>$k</dt><dd>$v</dd>"; ?>
</dl>

<h1>Post</h1>
<dl>
<?php foreach ($_POST as $k => $v) echo "<dt>$k</dt><dd>$v</dd>"; ?>
</dl>

<form name="theForm" method="<?php echo isset($_GET['method']) ? $_GET['method'] : 'get'; ?>" action="<?php echo $_SERVER['SCRIPT_NAME']; ?>">
    <input type="text" name="method" />
    <input type="submit" name="action" value="Button 1" onclick="alert('Button 1'); return true" />
    <input type="text" name="stuff" />
    <input type="submit" name="action" value="Button 2" onclick="alert('Button 2'); return true" />
    <input type="button" value="submit" onclick="document.theForm.submit();" />
</form>

</body></html>

当前回答

现在可以使用Flexbox解决这个问题:

HTML

<form>
    <h1>My Form</h1>
    <label for="text">Input:</label>
    <input type="text" name="text" id="text"/>

    <!-- Put the elements in reverse order -->
    <div class="form-actions">
        <button>Ok</button> <!-- Our default action is first -->
        <button>Cancel</button>
    </div>
</form>

CSS

.form-actions {
    display: flex;
    flex-direction: row-reverse; /* Reverse the elements inside */
}

解释

使用Flexbox,我们可以通过使用CSS规则:flex-direction: row-reverse来反转使用display: flex的容器中的元素顺序。这不需要CSS或隐藏元素。对于不支持Flexbox的旧浏览器,他们仍然得到一个可行的解决方案,但元素不会被反转。

Demo

http://codepen.io/Godwin/pen/rLVKjm

其他回答

If you submit the form via JavaScript (i.e., formElement.submit() or anything equivalent), then none of the submit buttons are considered successful and none of their values are included in the submitted data. (Note that if you submit the form by using submitElement.click() then the submit that you had a reference to is considered active; this doesn't really fall under the remit of your question since here the submit button is unambiguous but I thought I'd include it for people who read the first part and wonder how to make a submit button successful via JavaScript form submission. Of course, the form's onsubmit handlers will still fire this way whereas they wouldn't via form.submit() so that's another kettle of fish...)

If the form is submitted by hitting Enter while in a non-textarea field, then it's actually down to the user agent to decide what it wants here. The specifications don't say anything about submitting a form using the Enter key while in a text entry field (if you tab to a button and activate it using space or whatever, then there's no problem as that specific submit button is unambiguously used). All it says is that a form must be submitted when a submit button is activated. It's not even a requirement that hitting Enter in e.g. a text input will submit the form.

我相信Internet Explorer会选择在源代码中首先出现的提交按钮;我有一种感觉,Firefox和Opera会选择标签索引最低的按钮,如果没有其他定义,就会退回到第一个定义的按钮。关于提交是否具有非默认值属性IIRC,也存在一些复杂性。

The point to take away is that there is no defined standard for what happens here and it's entirely at the whim of the browser - so as far as possible in whatever you're doing, try to avoid relying on any particular behaviour. If you really must know, you can probably find out the behaviour of the various browser versions, but when I investigated this a while back there were some quite convoluted conditions (which of course are subject to change with new browser versions) and I'd advise you to avoid it if possible!

我使用的另一种解决方案是在表单中只设置一个按钮,并伪造其他按钮。

这里有一个例子:

<form>
  <label for="amount">Amount of items</label>
  <input id="amount" type="text" name="amount" />
  <span id="checkStock" class="buttonish">Check stock</span>
  <button type="submit" name="action" value="order">Place order</button>
</form>

然后我将span元素的样式设置为看起来像一个按钮。JavaScript侦听器观察跨度,并在单击后执行所需的操作。

这并不一定适用于所有情况,但至少很容易做到。

要确定按enter键时按下了哪个按钮,可以用type="submit"标记它,其他按钮用type="button"标记它们。例如:

<input type="button" value="Cancel" />
<input type="submit" value="Submit" />

抱歉,当我写这个答案时,我想的是一般意义上的提交按钮。下面的答案不是关于多个type="submit"按钮,因为它只留下一个type="submit",而把另一个改为type="button"。我把答案留在这里作为参考,以防帮助可以更改表单类型的人。

从HTML 4规范:

如果一个表单包含多个提交按钮,只有激活 提交按钮成功。

这意味着如果有多个提交按钮且没有激活(单击),则没有一个提交按钮会成功。

我认为这是有道理的:

想象一个有多个提交按钮的巨大表单。在顶部,有一个“删除这条记录”按钮,然后有很多输入,在底部有一个“更新这条记录”按钮。当用户在表单底部的字段中按Enter时,他/她永远不会怀疑他/她从顶部隐式地按下了“删除此记录”。

因此,我认为使用用户没有定义(点击)的第一个按钮或任何其他按钮都不是一个好主意。不过,浏览器当然也在这么做。

我有一个带有11个提交按钮的表单,当用户按下Enter键时,它总是使用第一个提交按钮。我在别处读到过,在一个表单上有多个提交按钮不是一个好主意(糟糕的做法),最好的方法是将您想要的按钮作为默认按钮,作为表单上唯一的提交按钮。其他按钮应该变成“TYPE=BUTTON”,并添加一个onClick事件,用JavaScript调用自己的提交例程。就像这样:

<SCRIPT Language="JavaScript">
function validform()
{
  // Do whatever you need to validate the form, and return true or false accordingly
}

function mjsubmit()
{
  if (validform()) { document.form1.submit(); return true;}
  return false;
}
</SCRIPT>
<INPUT TYPE=BUTTON NAME="button1" VALUE="button1" onClick="document.form1.submitvalue='button1'; return mjsubmit();">
<INPUT TYPE=BUTTON NAME="button2" VALUE="button2" onClick="document.form1.submitvalue='button2'; return mjsubmit();">
<INPUT TYPE=SUBMIT NAME="button3" VALUE="button3" onClick="document.form1.submitvalue='button3'; return validform();">
<INPUT TYPE=BUTTON NAME="button4" VALUE="button4" onClick="document.form1.submitvalue='button4'; return mjsubmit();">

这里,button3是默认的,尽管您是通过编程方式提交表单和其他按钮,但mjsubmit例程将验证它们。