由于空字段，如何使用javascript来阻止表单提交？
问题描述：
如何在javascript中创建脚本以输出错误并阻止表单中的空字段提交表单？假设表单名称为form，输入名称为name。我在使用PHP时遇到麻烦并不总是正确处理空字段，所以我希望将其作为备份。感谢任何帮助。
How do I make a script in javascript to output an error and prevent form submission with empty fields in the form? Say the form name is "form" and the input name is "name". I have been having some trouble with PHP not always handling the empty fields correctly, so I would like this as a backup. Any help is appreciated, thanks.
答
HTML代码： -
HTML Code :-
<form name='form'>
<input type="button" onclick="runMyFunction()" value="Submit form">
</form>
Javascript代码： -
Javascript Code :-
function runMyFunction()
{
if (document.getElementsByName("name")[0].value == "")
{
alert("Please enter value");
}
else
{
var form= document.getElementsByName("form")[0];
form.submit();
}
}