Canvas 文字换行，设定超出的部分 省略号代替

data: {
    powerCodeImage: "",
    activetityTitle: "《大卫，不可以！》绘本儿童剧阅读系利展会",
    activetityTitle1: "活动时间:",
    activeDate: "2018/10/10",
    activeTime: "15:30",
    activeNote1: "方式1：长按识别授权码",
    activeNote2: "方式2：直接扫描该授权码",
    temp :'',
    row :[],
    chr:'',
  },

/**
   * 绘制文字
   */
  word: function (wordText){
    var _this= this,
    //同过Canvas.measureText() 获取文本的长度
   changdu = myCtx.measureText(wordText).width;
    //拆分文本
    _this.data.chr = _this.data.activetityTitle.split('');
    for (var i = 0; i < _this.data.chr.length; i++) {
        //判断temp字符串的width是否小于 提前设定的长度
      if (myCtx.measureText(_this.data.temp).width < 300) {
           小于，则把当前的字符串拼接 temp
        _this.data.temp += _this.data.chr[i]
      } else {
        i--;
        _this.data.row.push(_this.data.temp)
        _this.data.temp = "";
      }
    }
    _this.data.row.push(_this.data.temp);
    if (_this.data.row.length > 1) {
      var rowCut = _this.data.row.slice(0, 2);
      var rowPart = rowCut[1];
      var test = "";
      var empty = [];
      for (var a = 0; a < rowPart.length; a++) {
        if (myCtx.measureText(test).width < 300) {
          test += rowPart[a];
        }
        else {
          break;
        }
      }
      empty.push(test);
      if (_this.data.row.length > 2) {
        var group = empty[0] + "..."
      } else {
        var group = empty[0]
      }
      rowCut.splice(1, 1, group);
      _this.data.row = rowCut;
      for (var b = 0; b < _this.data.row.length; b++) {
        myCtx.fillText(_this.data.row[b], 35, 30 + b * 30, 300);
      }
    } else {
      myCtx.fillText(_this.data.activetityTitle, 35, 30, 300);
    }
  }