代码如下：

  displayProbabilityByOne(probabilityTexts:string) {
    let curIndex = 0
    let probabilityTimer = setInterval(() => {
      //先清空
      this.textResult = probabilityTexts.substr(0, curIndex);
      console.log("DebugLog:  this.textResult: " + this.textResult)
      if (curIndex < probabilityTexts.length) {
        curIndex++
      }
      else {
        clearInterval(probabilityTimer);
      }
    }, 20)    //20是时间间隔
  }

参考：
VUE3+TS实现文本打字机效果
js实现页面打字机，动态显示文字