代码片段不起作用
[英]Snippet of code not working
问题描述
Below is a simplified snippet of code from a form validation script. 
下面是表单验证脚本的简化代码片段。 It does not work... 这是行不通的...
When the form is submitted and the user has left "inputfield" empty, the first alert pops up. 提交表单并且用户将“inputfield”留空时，会弹出第一个警报。 After the user has entered something in "inputfield", the second alert pops up when the user clicks submit. 用户在“inputfield”中输入内容后，当用户单击“提交”时，会弹出第二个警报。
Afterwards, the script should return false and continue validation. 之后，脚本应返回false并继续验证。 I need both alerts to be included in the same else if. 我需要将两个警报包括在同一个其他内容中。 What am I doing wrong? 我究竟做错了什么？ The alerts do not show and the form validation ignores this portion of code... 警报没有显示，表单验证忽略了这部分代码......
} else if (myform.inputfield.value=="") {
alert ('Please enter something in the text field!');
}
if (myform.inputfield.value!=="") {
alert ('Thank you for entering something in the field!');
return false;
}
2 个解决方案
解决方案1
1 2014-04-09 06:22:15
I agree rather use document.getElementById, or jQuery $('#input1').val() 我同意使用document.getElementById或jQuery $（'＃input1'）。val（）
<script type="text/javascript">
function validate() {
if (document.getElementById('input1').value == "") {
alert('Please enter something in the text field!');
}
if (document.getElementById('input2') !== "") {
alert('Thank you for entering something in the field!');
return false;
}
}
</script>
</head>
<body>
<form onsubmit="return validate()">
<input id="input1" />
<input id="input2" />
<input type="submit" value="OK" />
</form>
</body>
You might have a return statement before the specified line of code? 您可能在指定的代码行之前有一个return语句？
解决方案2
1 已采纳 2014-04-09 06:55:18
Isn't it better to declare a flag and return the it as a result? 声明一个标志并返回它是不是更好？ take the following sample into account: 考虑以下示例：
var validationResult = true;
...
} else if (myform.inputfield.value=="") {
validationResult = false;
alert ('Please enter something in the text field!');
}
if (myform.inputfield.value!=="") {
alert ('Thank you for entering something in the field!');
validationResult = false;
}
return validationResult;
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