Javascript -禁用提交按钮，直到3个字段不为空

Question

我有这个几乎工作位:http://jsfiddle.net/HFzkW/我的代码是这样的:

<div id="cform-container">
<div class="alignleft" id="cform">
    <form action="<?php print site_url('/sent'); ?>" method="POST" >
    <input type="hidden" name="Contact-Form" value="contact-form" />
        <div class="cform-row">
            <div class="alignleft cform-label"><label for="yn">Your Name</label><span id="star5">*</span></div>
            <div class="alignright cform-ti"><input type="text" name="yn" id="yn" /><br /><span id="namespan" value="0"></span></div>
            <div class="clearboth"></div>
        </div>
        <div class="cform-row">
            <div class="alignleft cform-label"><label for="cn">Company Name</label></div>
            <div class="alignright cform-ti"><input type="text" name="cn" id="cn" /></div>
            <div class="clearboth"></div>
        </div>
        <div class="cform-row">
            <div class="alignleft cform-label"><label for="em">Email Address</label><span id="star5">*</span></div>
            <div class="alignright cform-ti"><input type="text" name="em" id="em" /><br /><span id="emailspan" value="0"></span></div>
            <div class="clearboth"></div>
        </div>
        <div class="cform-row">
            <div class="alignleft cform-label"><label for="ph">Phone Number</label><span id="star5">*</span></div>
            <div class="alignright cform-ti"><input type="text" name="ph" id="ph" /><br /><span id="phonespan" value="0"></span></div>
            <div class="clearboth"></div>
        </div>
        <div class="cform-row">
            <div class="alignleft cform-label"><label for="ct">Industry</label></div>
            <div class="alignright cform-ti"><input type="text" name="ct" id="ct" /></div>
            <div class="clearboth"></div>
        </div>
        <div class="cform-row">
            <div class="alignleft cform-label"><label for="msg">Message</label></div>
            <div class="alignright cform-ti"><textarea name="msg" id="msg"></textarea></div>
            <div class="clearboth"></div>
        </div>
        <div id="cform-btn"><input type="submit" value="Submit" /></div>
    </form>
</div>
<script id="source" language="javascript" type="text/javascript">
 $(function(){  
    $("input[type=submit]").attr("disabled", "disabled");
    $("#em").blur(function() 
            {
             var emailReg = /^([w-.]+@([w-]+.)+[w-]{2,4})?$/;  
             var emailaddress = $("#em").val();
             if(!emailReg.test(emailaddress) | emailaddress=="") {
                $("#emailspan").html('<font color="#cc0000">Please enter valid Email address</font>');
             }else{
                $("#emailspan").html('<font color="#cc0000"></font>');  
                }
            });
    $("#yn").blur(function() 
            {
             var namefield = $("#yn").val();
             if(namefield=="") {
                $("#namespan").html('<font color="#cc0000">Please enter your name</font>');  
             }else{
                $("#namespan").html('<font color="#cc0000"></font>');  
                }
            });                                 
    $("#ph").blur(function() 
            {
             var phonefield = $("#ph").val();
             if(phonefield=="") {
                $("#phonespan").html('<font color="#cc0000">Please enter your name</font>');  
             }else{
                $("#phonespan").html('<font color="#cc0000"></font>');  
                }
            });
$('input, textarea').change(function(){
    var validation;
    var email = $("#em").val();
    var name = $("#yn").val();
    var phone = $("#ph").val();
    if ( email == "" && name == "" && phone == "" ) {
    validation = false;
    } else if ( email != "" && name != "" && phone != "" ) {
    alert ("variables"+email+name+phone);
    validation = true;
    }
    if (validation = true) {
    $("input[type=submit]").removeAttr("disabled"); 
    } else {
    $("input[type=submit]").attr("disabled", "disabled");
    }
});
});

我不能让它完全工作。当用户输入其中一个字段(如您的姓名)时，提交按钮不再被禁用。

我想保持Submit按钮禁用，直到满足所有3个'required'字段。我认为代码是非常清楚的-但它仍然不能工作。

此外，它在JSFiddle中工作，但在我试图让它工作的Wordpress网站上不工作。

Answer 1

试着切换手到ors。小心你的逻辑，试着大声说出来，看看它是否有意义:

Email为空，name为空，phone为空，则验证为假。您实际想要的是说，如果任何字段为空，则验证为假。

if ( email == "" || name == "" || phone == "" ) {
validation = false;
} else if ( email != "" && name != "" && phone != "" ) {
alert ("variables"+email+name+phone);
validation = true;
}

同样，您在if语句中设置了validation=true。这将始终返回true。改成:if (validation == true) {

Answer 2

从我所看到的，我要做的第一件事来调试这个(代码有点混乱，所以不是复制它，我会给你一些指导方针)。

代替

 if(validation = true )

试

 if(validation)

这是因为在没有任何参数的情况下，它将检查是否为false、undefined或null。同样的方法也可以用于电子邮件名和电话。

Answer 3

所以基本上:

<form id="myForm" onfocus="submitButton("myForm);">
  <input type="text" name="name" placeholder="Name">
  <input type="text" name="email" placeholder="Email">
  <input type="text" name="phone" placeholder="Phone">
</form>

和

function submitButton(formID){
  var formObject = document.getElementById(formID);
  var name = formObject.name.value;
  var email = formObject.email.value;
  var phone = formObject.phone.value;
  if (name && email && phone) {
    showSubmitButton();
  } else {
    //keep the button hidden
  }
}