Vue Components 数字键盘的实现

let inputElement = document.getElementsByTagName("input");
  [...inputElement].forEach(ipele => {
   ipele.addEventListener("focus", function(e) {
    $this.inputTarget = e.target;
    let scrollTop =
     window.pageYOffset ||
     document.documentElement.scrollTop ||
     document.body.scrollTop;
    let scrollLeft =
     window.pageXOffset ||
     document.documentElement.scrollLeft ||
     document.body.scrollLeft;
    $this.NumberkeyBoardStyle =
     ":" +
     (e.target.getBoundingClientRect(). +
      scrollTop +
      e.target.offsetHeight) +
     "px;left:" +
     (e.target.getBoundingClientRect().left +
      scrollLeft +
      e.target.offsetWidth) +
     "px";
   });
   ipele.addEventListener("blur", function(e) {
    $this.inputTarget = null;
    $this.NumberkeyBoardStyle = "display:none";
   });
  });

BoardNumberKeyDown(e) {
   if (e && e.preventDefault) {
    e.preventDefault();
   } else {
    window.event.returnValue = false;
    return false;
   }
  },

let inputTarget = this.inputTarget;
let Pointstart = inputTarget.selectionStart;
let PointEnd = inputTarget.selectionEnd;
let wordLength = inputTarget.value.length;
if (e.target.className == "numberTD" && e.target.innerText != "←") {
inputTarget.value =
 inputTarget.value.slice(0, Pointstart) +
 e.target.innerText +
 inputTarget.value.slice(PointEnd, wordLength);
//一个小数点和开头不能有小数点
inputTarget.value = inputTarget.value.replace(/^\./g, "");
inputTarget.value = inputTarget.value
 .replace(".", "$#$")
 .replace(/\./g, "")
 .replace("$#$", ".");
inputTarget.selectionStart = Pointstart + 1;
inputTarget.selectionEnd = Pointstart + 1;
//让光标显示在input可视区域
inputTarget.blur();
inputTarget.focus();

if (e.target.className == "numberTD" &&
  e.target.innerText == "←" &&
  //PointEnd==0时会复制整个input的value
  PointEnd != 0
  ) {
    inputTarget.value =
     inputTarget.value.slice(0, Pointstart - 1) +
     inputTarget.value.slice(PointEnd, wordLength);
    inputTarget.selectionStart = Pointstart - 1;
    inputTarget.selectionEnd = Pointstart - 1;
    //让光标显示在input可视区域
    inputTarget.blur();
    inputTarget.focus();
   }