jquery - 如果选择了选项，则使用 Jquery 禁用提交按钮

Question

我有一个带有四个选择字段的简单表单。如果在任何表单字段上选择"is"，则需要禁用提交按钮，并且应该出现一个隐藏的 div。这是我的标记的示例:

<form>
I have read the information on the product(s)<select name="field4"> <option value="Yes">Yes</option> <option value="No">No</option> </select>

Do you have any allergies to any ingredients in product(s)?
 <select name="field5"><option value="Yes">Yes</option> <option value="No">No</option> </select>

Are you pregnant?
 <select name="field6"> <option value="Yes">Yes</option> <option value="No">No</option> </select>

Have you ever used this type of product and had undesirable results?
 <select name="field7"> <option value="Yes">Yes</option> <option value="No">No</option> </select>

<input name="cmdSubmit" type="submit" value="Submit" />
</form>


<div style="display:none;">Hidden div only to appear if any of the four dropdowns are marked YES.</div>

感谢您在这方面的帮助。我是一名 jquery 新手，正在尽我最大的努力学习。

Answer 1

我不完全理解您构建表单的方式的业务逻辑和您的要求，但是......根据您在这里所说的内容就是我要做的。

1. 编写函数来检查所有选项、更改禁用/启用提交、显示/隐藏 div
2. 加载时调用函数
3. 每次选项值更改时调用函数检查所有选项

.

checkOptions();
$("select").change(checkOptions);

function checkOptions() {
  var yesFound = false;
  $("select").each(function(index, element) {
    if ( $(element).val() == "Yes" ) {
      yesFound = true;
    }
  });

  if (yesFound) {
    $("#hidden-div").show();
    $("input[type=Submit]").attr("disabled","disabled");
  } else {
    $("#hidden-div").hide();
    $("input[type=Submit]").removeAttr("disabled");
  };
}

稍微修改了 HTML:

<form>
  <select name="field4"> 
    <option value="Yes">Yes</option>
    <option value="No">No</option>
  </select> I have read the information on the product(s)<br/>
  <select name="field5">
    <option value="Yes">Yes</option>
    <option value="No">No</option>
  </select> Do you have any allergies to any ingredients in product(s)?<br/>
  <select name="field6">
    <option value="Yes">Yes</option>
    <option value="No">No</option>
  </select> Are you pregnant?<br/>
  <select name="field7">
    <option value="Yes">Yes</option>
    <option value="No">No</option>
  </select> Have you ever used this type of product and had undesirable results?<br/>
  <br/>
  <input name="cmdSubmit" type="submit" value="Submit" />
</form>
<div id="hidden-div" style="display:none;">Hidden div only to appear if any of the four dropdowns are marked YES.</div>

示例网页:

http://mikegrace.s3.amazonaws.com/forums/stack-overflow/example-disable-submit-dynamically.html

加载时:

所有选项均为“否”，只有一个:

所有选项"is":