如何验证JavaScript中的电子邮件字段？

Question

这是我使用的表单验证脚本：

<script language="JavaScript"> 

function formCheck(formobj){ 
    var fieldRequired = Array("Name", "Email", "Phone", "comments"); 
    var fieldDescription = Array("Name", "Email", "Phone", "Comments"); 
    var alertMsg = "Please complete the following fields:\n"; 

    var l_Msg = alertMsg.length; 

    for (var i = 0; i < fieldRequired.length; i++){ 
     var obj = formobj.elements[fieldRequired[i]]; 
     if (obj){ 
      switch(obj.type){ 
      case "select-one": 
       if (obj.selectedIndex == -1 || obj.options[obj.selectedIndex].text == ""){ 
        alertMsg += " - " + fieldDescription[i] + "\n"; 
       } 
       break; 
      case "select-multiple": 
       if (obj.selectedIndex == -1){ 
        alertMsg += " - " + fieldDescription[i] + "\n"; 
       } 
       break; 
      case "text": 
      case "textarea": 
       if (obj.value == "" || obj.value == null){ 
        alertMsg += " - " + fieldDescription[i] + "\n"; 
       } 
       break; 
      default: 
      } 
      if (obj.type == undefined){ 
       var blnchecked = false; 
       for (var j = 0; j < obj.length; j++){ 
        if (obj[j].checked){ 
         blnchecked = true; 
        } 
       } 
       if (!blnchecked){ 
        alertMsg += " - " + fieldDescription[i] + "\n"; 
       } 
      } 
     } 
    } 

    if (alertMsg.length == l_Msg){ 
     return true; 
    }else{ 
     alert(alertMsg); 
     return false; 
    } 
} 
// --> 
</script> 


<form onsubmit="return formCheck(this);" action="/capture.weblead" method="post"> 
First Name: <input type=text name="FirstName" size="25"><br> 
Last Name: <input type=text name="LastName" size="25"><br> 
<input type=submit value="Submit Form"> 
</form> 

这只是它不用于验证真实的电子邮件地址的伟大工程。如何改变这种形式，以便它呢？

该脚本不能包含任何美元符号，否则Tomcat（我的服务器环境）崩溃。

Answer 1

我会建议你使用jQuery和验证插件：

http://bassistance.de/jquery-plugins/jquery-plugin-validation/

它的灵活，可靠和易于使用。

Answer 2

这是一个快速和肮脏的解决方案。修改emailRegexp变量的值以满足您的需求。这里已经有一些例子。正如波蒂指出的那样，假阳性通常比假阴性通常要好。

function formCheck(formobj){ 
    var fieldRequired = Array("Name", "Email", "Phone", "comments"); 
    var fieldDescription = Array("Name", "Email", "Phone", "Comments"); 
    var alertMsg = "Please complete the following fields:\n"; 
    var emailRegexp =/@/; 

    var l_Msg = alertMsg.length; 

    for (var i = 0; i < fieldRequired.length; i++){ 
     var obj = formobj.elements[fieldRequired[i]]; 
     if (obj){ 
      switch(obj.type){ 
      case "select-one": 
       if (obj.selectedIndex == -1 || obj.options[obj.selectedIndex].text == ""){ 
        alertMsg += " - " + fieldDescription[i] + "\n"; 
       } 
       break; 
      case "select-multiple": 
       if (obj.selectedIndex == -1){ 
        alertMsg += " - " + fieldDescription[i] + "\n"; 
       } 
       break; 
      case "text": 
      case "textarea": 
       if (obj.value == "" || 
        obj.value == null || 
        (fieldRequired[i] == "Email" && !obj.value.match(emailRegexp))) 
       { 

        alertMsg += " - " + fieldDescription[i] + "\n"; 
       } 


       break; 
      default: 
      } 
      if (obj.type == undefined){ 
       var blnchecked = false; 
       for (var j = 0; j < obj.length; j++){ 
        if (obj[j].checked){ 
         blnchecked = true; 
        } 
       } 
       if (!blnchecked){ 
        alertMsg += " - " + fieldDescription[i] + "\n"; 
       } 
      } 
     } 
    } 

    if (alertMsg.length == l_Msg){ 
     return true; 
    }else{ 
     alert(alertMsg); 
     return false; 
    } 
} 

Answer 3

您可以在JavaScript

function is_email(email){  
var emailReg = /^[a-zA-Z0-9._-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,4}$/; 
return emailReg.test(email); } 

http://richwd.com/email-javascript