Javascript 动态检查的单选按钮，基于“值”属性，不检查
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Dynamically checked radio button, based on 'value' attribute, not checking
提问by Gideon
Trying to get a form to load pages with the previously checked radios already checked (upon a fresh load).
试图获取一个表单来加载先前检查过的无线电已经检查过的页面（在新加载时）。
The submissions of that page are held as php variables which I can pass into the javascript, the rest should be simple, but it's not working for me.
该页面的提交作为 php 变量保存，我可以将其传递给 javascript，其余的应该很简单，但它对我不起作用。
My code:
我的代码：
<div class="question">
<label for="sv_213">Question?</label>
<input
class="radio"
type="radio"
value="Yes"
name="sv_213"
/>Yes
<input
class="radio"
type="radio"
value="No"
name="sv_213"
/>No
</div>
My javascript:
我的javascript：
$(function() {
var 3 = Yes;
$("input[name='sv_213'][value="3"]").attr('checked', true);
});?
In the above js the
在上面的js中
var 3 = <dynamically generated content>
Such that it is set equal to the value of the radio button that was checked
这样它就被设置为等于被选中的单选按钮的值
Here is a js fiddle with it not working: http://jsfiddle.net/CW8AC/
这是一个 js 小提琴，它不起作用：http: //jsfiddle.net/CW8AC/
Many thanks for any help.
非常感谢您的帮助。
Incidentally my code is based on this, previously asked question: Set selected radio from radio group with a value
顺便说一句，我的代码基于此，先前提出的问题： Set selected radio from radio group with a value
回答by keithwyland
You need quotes around your value "Yes", since this is a string, and not a boolean or number.
您的值“是”需要引号，因为这是一个字符串，而不是布尔值或数字。
var 3 = "Yes";
Also, you need to add the variable into the selector with +'s like this:
此外，您需要使用 + 将变量添加到选择器中，如下所示：
$("input[name=sv_213][value="+3+"]").attr('checked', true);
Updated fiddle, working: http://jsfiddle.net/CW8AC/1/
更新小提琴，工作：http: //jsfiddle.net/CW8AC/1/
Full js code:
完整的js代码：
$(function() {
var 3 = "Yes";
$("input[name=sv_213][value="+3+"]").attr('checked', true);
});
Update:## Since jQuery 1.6, you can also use the .prop method with a boolean value (this should be the preferred method):
更新：## 从 jQuery 1.6 开始，您还可以使用带有布尔值的 .prop 方法（这应该是首选方法）：
$("input[name=sv_213][value="+3+"]").prop('checked', true);
in my case, the .attr() method didnt worked for dynamically selecting the radio button whereas .prop() did.
在我的例子中， .attr() 方法不能用于动态选择单选按钮，而 .prop() 可以。
回答by Harry Stevens
And in D3, in case anyone was wondering.
在 D3 中，以防万一有人想知道。
d3.selectAll("input[name='sv_213'][value=" + 3 + "]").property("checked", true);
