JQuery让input从disabled变成enabled

1. document.getElementByIdx_x("removeButton").disabled = false;//普通Js写法  
2. $("#removeButton").removeAttr("disabled");//要变成Enable，JQuery只能这么写  
3. $("#removeButton").attr("disabled","disabled");//再改成disabled  
4. $(this).attr("readonly", "readonly").css("color", "GrayText");灰色文本框

JQuery让input从disabled变成enabled