只適用於一個輸入按鈕

Question

我如何使用「id」僅應用禁用/啓用按鈕，如果只有第二個按鈕被點擊複選框，因爲我需要它來打開和關閉取決於if點擊複選框。凡爲第一個按鈕將永遠是第二提交按鈕的

http://jsfiddle.net/BPhZe/2122/

<h1>Button should be enabled if at least one checkbox is checked</h1> 

<form> 
    <div> 
     <input type="checkbox" name="option-1" id="option-1"> <label for="option-1">Option 1</label> 
    </div> 
    <div> 
     <input type="checkbox" name="option-2" id="option-2"> <label for="option-2">Option 2</label> 
    </div> 
    <div> 
     <input type="submit" id="sub1" value="Do thing"> 
    </div> 

    <div> 
     <input type="checkbox" name="here" id="option-12"> <label for="option-2">Option 3</label> 
    </div> 
    <div> 
     <input type="checkbox" name="now" id="option-22"> <label for="option-2">Option 4</label> 
    </div> 

    <div> 
     <input type="submit" id="sub2" value="Do thing" disabled="true"> 
    </div> 
</form> 

var checkboxes = $("input[type='checkbox']"), 
    submitButt = $("input[type='submit']"); 

checkboxes.click(function() { 
    submitButt.attr("disabled", !checkboxes.is(":checked")); 
}); 

Answer 1

使用id代替input[type='submit']。

var submitButt = $("#sub2"); 

FIDDLE DEMO

Answer 2

var checkboxes = $("input[type='checkbox']"), 
    submitButt2 = $("#sub2"); 

checkboxes.click(function() { 
    submitButt2.attr("disabled", !checkboxes.is(":checked")); 
});