Question

我正在尝试使用javascript验证表单，但是当字段为空时，它会直接转到下一页而不是警报。

<script type="text/javascript">
validateForm()  
{    
    valid = true;   
    if  
        (document.contactForm.name.value == "") 
    {
        alert("Please enter your Name.");   
        valid = false;  
    }   
    if (document.contactForm.Contact.value== "")
    {
        alert("Please enter your contact details");
        valid = false;
    }       
    return valid;
}
  <form name="contactForm" method="post" action="confirmation.html" 
        onsubmit="return validateForm()" >
    <table>
      <tr>
        <td align="right">Name:</td>
        <td align="left"><input type="text" size="40" name="name" id="name" 
                                onblur="return  validateForm();"/></td>
      </tr>
      <tr>
        <td align="right">Contact number:</td>
        <td align="left"><input type="text" name="Contact" id="Contact"  
                                onblur="return validateForm();"/></td>
      </tr>
      <tr>
        <td align="right">Address:</td>
        <td align="left"><TEXTAREA NAME=“txtremarks" size="255"></TEXTAREA></td>
                                                               </tr>
<tr>
  <td>submit here</td>
  <td><input type="submit" name="send" value="Submit" /></td>
</tr>
</table>
</form>

它应该显示错误

Answer 1

该行：

validateForm()

应该是：

function validateForm()

DEMO

Answer 2

不要忘记将validateForm方法附加到onsubmit事件的html表单，也必须返回true / false

<form onsumbit="return validateForm();">
...
</form>

Answer 3

<script>

function validateForm(theForm)
{


    if (theForm.elementname.value == "")
  {
    alert("please enter element name value");
    theForm.elementname.focus();
    return (false);
  }

  return true;

}

</script>

<form method="post" action="iaction.php" onsubmit="return validateForm(this)" >

使用javascript登录验证

3 个答案: