问题描述：

在IE8及以下版本时，点击label标签无法自动触发checkbox的click事件，导致无法产生希望的效果。

 原HTML代码：

 <div class="col-sm-2">
    <label><input type="checkbox"  value="申请检查" name="menu" class="cbr cbr-blue">申请检查</label>
 </div>

$("input:checkbox[name='menu']").each(function (index, element) {
        $(this).click(function () {
          if ($(this).attr("checked") != undefined) {
            $(this).removeAttr("checked");
            var menues = $("#selmenues").val();
            var arrMenues = menues.split(',');
            if (arrMenues.length > 0) {
              arrMenues.forEach(function (val) {
                //console.log(element.value);
                if (element.value == val) {
                  arrMenues.splice($.inArray(val, arrMenues), 1);
                }
              });
              menues = "";
              arrMenues.forEach(function (val) {
                menues += val + ',';
              });
              menues = menues.substring(0, menues.length - 1)
              //console.log(menues);
              $("#selmenues").val(menues);
              //console.log($("#selmenues").val());
            }

          } else {
            $(this).attr("checked", "checked");
            var menues = $("#selmenues").val();
            var arrMenues = menues.split(',');
            if (arrMenues.length > 0) {
              arrMenues.push($(this).val());
              menues = "";
              arrMenues.forEach(function (val) {
                menues += val + ',';
              });
              menues = menues.substring(0, menues.length - 1)
              //console.log(menues);
            }
            else {
              menues += $(this).val() + ',';
            }
            $("#selmenues").val(menues);
            //console.log($("#selmenues").val());
          }
        })
      });

根本原因：因为ie8不支持事件传递，当点击蓝色的框框时，触发了label的click事件而并没有触发其中checkbox标签的click事件。

解决方式：我们可以修改html代码，将label标签和checkbox标签通过id属性关联，同时给label加上name属性，将事件处理放在label标签上。

新HTML代码：

 <div class="col-sm-2">
   <label name="lbl_menu" ><input type="checkbox"  value="申请检查" name="menu" class="cbr cbr-blue">申请检查</label>
</div>

$("label[name='lbl_menu']").each(function (index, element) {
        $(this).click(function () {
          //console.log($('input#chk_' + this.id).attr("checked"));
          if ($('input#chk_' + this.id).attr("checked") != undefined) {
            $('input#chk_' + this.id).removeAttr("checked");
            //$('input#chk_' + this.id).trigger("click");
            $('div').filter('.cbr-replaced.cbr-blue').eq(index).removeClass('cbr-checked');
            var menues = $("#selmenues").val();
            var arrMenues = menues.split(',');
            if (arrMenues.length > 0) {
              arrMenues.forEach(function (val) {
                //console.log(element.value);
                if (element.value == val) {
                  arrMenues.splice($.inArray(val, arrMenues), 1);
                }
              });
              menues = "";
              arrMenues.forEach(function (val) {
                menues += val + ',';
              });
              menues = menues.substring(0, menues.length - 1)
              //console.log(menues);
              $("#selmenues").val(menues);
              //console.log($("#selmenues").val());
            }
          } else {
            $('input#chk_' + this.id).attr("checked", "checked");
            // console.log($('input#chk_' + this.id).attr("checked"));
            //$('input#chk_' + this.id).trigger("click");
            // console.log($('.cbr-replaced.cbr-blue')[index]);
            $('div').filter('.cbr-replaced.cbr-blue').eq(index).addClass('cbr-checked');
            var menues = $("#selmenues").val();
            var arrMenues = menues.split(',');
            if (arrMenues.length > 0) {
              arrMenues.push($('input#chk_' + this.id).val());
              menues = "";
              arrMenues.forEach(function (val) {
                menues += val + ',';
              });
              menues = menues.substring(0, menues.length - 1)
              //console.log(menues);
            }
            else {
              menues += $('input#chk_' + this.id).val() + ',';
            }
            $("#selmenues").val(menues);
            //console.log($("#selmenues").val());
          }
        })
      });