js 自执行函数转d.ts之搬砖的代价.

重复造轮子不可取,可是从这辆车的轮子换到另一不同品牌的车上, 也是一场重新塑造的过程.融合这块,往往也费时时费力,

很多js 比如fabric.js 画图插件,功能很完善了. 用到ts 项目中,ts项目内无vue环境.

只能通过 js 加一个 d.ts  声明使用 fabric 或者使用fabric的测试js .比如网上有有个测试 就是一个自行执行函数的测试例子js

(function() {
  var $ = function(id){return document.getElementById(id)};
  var canvas = this.__canvas = new fabric.Canvas('c', {
    isDrawingMode: true
  });
  fabric.Object.prototype.transparentCorners = false;

  var drawingModeEl = $('drawing-mode'),
    drawingOptionsEl = $('drawing-mode-options'),
    drawingColorEl = $('drawing-color'),
    drawingShadowColorEl = $('drawing-shadow-color'),
    drawingLineWidthEl = $('drawing-line-width'),
    drawingShadowWidth = $('drawing-shadow-width'),
    drawingShadowOffset = $('drawing-shadow-offset'),
    clearEl = $('clear-canvas');

  clearEl.onclick = function() { canvas.clear() };

  drawingModeEl.onclick = function() {
    canvas.isDrawingMode = !canvas.isDrawingMode;
    if (canvas.isDrawingMode) {
      drawingModeEl.innerHTML = 'Cancel drawing mode';
      drawingOptionsEl.style.display = '';
    }
    else {
      drawingModeEl.innerHTML = 'Enter drawing mode';
      drawingOptionsEl.style.display = 'none';
    }
  };

  if (fabric.PatternBrush) {
    var vLinePatternBrush = new fabric.PatternBrush(canvas);
    vLinePatternBrush.getPatternSrc = function() {

      var patternCanvas = fabric.document.createElement('canvas');
      patternCanvas.width = patternCanvas.height = 10;
      var ctx = patternCanvas.getContext('2d');

      ctx.strokeStyle = this.color;
      ctx.lineWidth = 5;
      ctx.beginPath();
      ctx.moveTo(0, 5);
      ctx.lineTo(10, 5);
      ctx.closePath();
      ctx.stroke();

      return patternCanvas;
    };

    var hLinePatternBrush = new fabric.PatternBrush(canvas);
    hLinePatternBrush.getPatternSrc = function() {

      var patternCanvas = fabric.document.createElement('canvas');
      patternCanvas.width = patternCanvas.height = 10;
      var ctx = patternCanvas.getContext('2d');

      ctx.strokeStyle = this.color;
      ctx.lineWidth = 5;
      ctx.beginPath();
      ctx.moveTo(5, 0);
      ctx.lineTo(5, 10);
      ctx.closePath();
      ctx.stroke();

      return patternCanvas;
    };

    var squarePatternBrush = new fabric.PatternBrush(canvas);
    squarePatternBrush.getPatternSrc = function() {

      var squareWidth = 10, squareDistance = 2;

      var patternCanvas = fabric.document.createElement('canvas');
      patternCanvas.width = patternCanvas.height = squareWidth + squareDistance;
      var ctx = patternCanvas.getContext('2d');

      ctx.fillStyle = this.color;
      ctx.fillRect(0, 0, squareWidth, squareWidth);

      return patternCanvas;
    };

    var diamondPatternBrush = new fabric.PatternBrush(canvas);
    diamondPatternBrush.getPatternSrc = function() {

      var squareWidth = 10, squareDistance = 5;
      var patternCanvas = fabric.document.createElement('canvas');
      var rect = new fabric.Rect({
         squareWidth,
        height: squareWidth,
        angle: 45,
        fill: this.color
      });

      var canvasWidth = rect.getBoundingRect().width;

      patternCanvas.width = patternCanvas.height = canvasWidth + squareDistance;
      rect.set({ left: canvasWidth / 2, top: canvasWidth / 2 });

      var ctx = patternCanvas.getContext('2d');
      rect.render(ctx);

      return patternCanvas;
    };

    var img = new Image();
    img.src = '../assets/honey_im_subtle.png';

    var texturePatternBrush = new fabric.PatternBrush(canvas);
    texturePatternBrush.source = img;
  }

  $('drawing-mode-selector').onchange = function() {

    if (this.value === 'hline') {
      canvas.freeDrawingBrush = vLinePatternBrush;
    }
    else if (this.value === 'vline') {
      canvas.freeDrawingBrush = hLinePatternBrush;
    }
    else if (this.value === 'square') {
      canvas.freeDrawingBrush = squarePatternBrush;
    }
    else if (this.value === 'diamond') {
      canvas.freeDrawingBrush = diamondPatternBrush;
    }
    else if (this.value === 'texture') {
      canvas.freeDrawingBrush = texturePatternBrush;
    }
    else {
      canvas.freeDrawingBrush = new fabric[this.value + 'Brush'](canvas);
    }

    if (canvas.freeDrawingBrush) {
      var brush = canvas.freeDrawingBrush;
      brush.color = drawingColorEl.value;
      if (brush.getPatternSrc) {
        brush.source = brush.getPatternSrc.call(brush);
      }
      brush.width = parseInt(drawingLineWidthEl.value, 10) || 1;
      brush.shadow = new fabric.Shadow({
        blur: parseInt(drawingShadowWidth.value, 10) || 0,
        offsetX: 0,
        offsetY: 0,
        affectStroke: true,
        color: drawingShadowColorEl.value,
      });
    }
  };

  drawingColorEl.onchange = function() {
    var brush = canvas.freeDrawingBrush;
    brush.color = this.value;
    if (brush.getPatternSrc) {
      brush.source = brush.getPatternSrc.call(brush);
    }
  };
  drawingShadowColorEl.onchange = function() {
    canvas.freeDrawingBrush.shadow.color = this.value;
  };
  drawingLineWidthEl.onchange = function() {
    canvas.freeDrawingBrush.width = parseInt(this.value, 10) || 1;
    this.previousSibling.innerHTML = this.value;
  };
  drawingShadowWidth.onchange = function() {
    canvas.freeDrawingBrush.shadow.blur = parseInt(this.value, 10) || 0;
    this.previousSibling.innerHTML = this.value;
  };
  drawingShadowOffset.onchange = function() {
    canvas.freeDrawingBrush.shadow.offsetX = parseInt(this.value, 10) || 0;
    canvas.freeDrawingBrush.shadow.offsetY = parseInt(this.value, 10) || 0;
    this.previousSibling.innerHTML = this.value;
  };

  if (canvas.freeDrawingBrush) {
    canvas.freeDrawingBrush.color = drawingColorEl.value;
    canvas.freeDrawingBrush.source = canvas.freeDrawingBrush.getPatternSrc.call(this);
    canvas.freeDrawingBrush.width = parseInt(drawingLineWidthEl.value, 10) || 1;
    canvas.freeDrawingBrush.shadow = new fabric.Shadow({
      blur: parseInt(drawingShadowWidth.value, 10) || 0,
      offsetX: 0,
      offsetY: 0,
      affectStroke: true,
      color: drawingShadowColorEl.value,
    });
  }
})();

翻译成ts 文件 各种的错,放弃,直接使用呢,那得生成一个 此js的d.ts .webpack打包的时候 会识别这个js不会编译,但此测试js必须有d.ts

这种用法估计网上很少, 整个过程就是跟编译器斗智斗勇啊..几近要放弃.后来瞎写一下,竟然成功了.

问题出在fabric 无法传递到 这个测试js中, 

/// <reference types="fabric"/> 引入到d.ts 编译器没给传递进去

后来 修改一下测试js加上参数传递 

还是提示fabric 未声明

/// <reference types="fabric"/> 引入到d.ts  这个代码也无效啊..
按照ztree 的方式也不行,ztree 用的jquery ,难道是因为jquery 是全局的导致吗.没细查.

几近放弃,在index.ts 的引用页中我看

import {fabric} from 'fabric'     fabric 灰白色,没有引用,直接给 markbar 的intMarkBar 一个未有的,无中生有的函数传递这个fabric 进去,竟然传递过去了.

总结猜猜 匿名函数后括弧内的参数,可以通过下边的方式就能传递进去.

import {fabric} from 'fabric'
import {initMarkBar} from "./markbar";

initMarkBar(fabric);

因为测试js是自执行匿名函数,也不需要留出外边调用的方法等.开始想用匿名改为添加一个命名.后未去做,先在d.ts内 为空,结果报错找不到模块

后在d.ts内任意加了个方法.结果不报错了.

 后记:尽管 test js 的方式也能用,毕竟还是个野路子.正规的方法就是npm fabric和types 文件后直接引用fabric ,使用fabric就可以了.test.js 只是证明对fabric不够熟悉,实际 测试了几个fabric ts实例 .也变得很简单.事物总是由模糊到熟练的过程.