jquery 多选框是否选中 jquery设置多选框选中

var checkboxVals = "";
  //遍历选中的选项
  $(".rig[type='checkbox']").each(function(){
    var checkFlag = false; //选中状态判断
      var val = $(this).attr("value"); //获取当前选中框的值
      $(this).click(function(){ //每点击一次触发一次值
        if(checkFlag){ //去勾
          $(this).attr("checked",false);
          checkboxVals = checkboxVals.replace(val + " ",""); //把 值+“” 替换成 “”
          checkFlag = false;
        }else{ //打勾
          $(this).attr("checked",true);
          checkboxVals += $(this).attr("value") + " ";  //为checkboxVals追加选中值
          checkFlag = true;
        }
        $(".sp").val(checkboxVals);
      })
  })

相应 html如下：

<div class="uploader blue">
      <label class="item vp"><span class="point">*</span>答案：</label>
      <textarea type="text" class="len sp" disabled="disabled" style="background-color:#eee"></textarea>
    </div>
    <br>

    <div class="all all0">
      <div class="uploader blue">      
        <label class="item">选项A<input type="radio" name="item" value="A" class="rig"></label>      
        <input type="text" class="filename"/>
        <input type="button" name="file" class="button" value="↑"/>
        <input type="file" size="30"/>
      </div>

      <div class="uploader blue">
        <label class="item">选项B<input type="radio" name="item" value="B" class="rig"></label>      
        <input type="text" class="filename"/>
        <input type="button" name="file" class="button" value="↑"/>
        <input type="file" size="30"/>
      </div>
      <div class="uploader blue">
        <label class="item">选项C<input type="radio" name="item" value="C" class="rig"></label> 
        <input type="text" class="filename"/>
        <input type="button" name="file" class="button" value="↑"/>
        <input type="file" size="30"/>
      </div>

      <div class="uploader blue">
        <label class="item">选项D<input type="radio" name="item" value="D" class="rig"></label> 
        <input type="text" class="filename"/>
        <input type="button" name="file" class="button" value="↑"/>
        <input type="file" size="30"/>
      </div>