如何点击添加按钮时添加按钮

   function getInsertBtn(){
              //创建input元素
        var inp = document.createElement("input");
        inp.type = "button";
        inp.addEventListener('click', function () {
            openLayerUrl('@Url.Action("PartialChildNodeView", "UEditor")');getBtnValue(this.value);printBtnValue()
        })
        let addButtonLength = Number($('.addButton>input').length)+1;
        inp.value = "知识点" + addButtonLength;
        $(".addButton").append($(inp))
         
    }

    <div>
        <input style="float:left"  />
    </div>

  <div class="addButton">
        <input  />
    </div>