javascript - 如何在 ionic 2/Angular2/typescript 中声明多个变量？

Question

我对 ionic2/Angular2/Typescript 完全陌生。我正在创建一个有八片的轮子。我在声明变量时遇到困难。如何声明多个变量？

在 javascript 中，我声明如下:

function rand(min, max) {
  return Math.random() * (max - min) + min;
}

    var color = ['#fbc','#f88','#fbc','#f88','#fbc','#f88', "#fbc", "#f67"];
    var label = ['10', '200', '50', '100', '5', '500', '0', "jPOT"];
    var slices = color.length;
    var sliceDeg = 360/slices;
    var deg = rand(0, 360);
    var speed = 0;
    var slowDownRand = 0;
    var ctx = canvas.getContext('2d');
    var width = canvas.width; // size
    var center = width/2;      // center
    var isStopped = false;
    var lock = false;

    function deg2rad(deg) {
      return deg * Math.PI/180;
    }

如何在 ionic2 中声明？

Answer 1

Ionic 2 运行在 Typescript 之上。因此您可以如下所示进行操作。

始终尝试使用let.You can read why here .

rand(min, max): your-return-type {
  return Math.random() * (max - min) + min;
}

    let color = ['#fbc','#f88','#fbc','#f88','#fbc','#f88', "#fbc", "#f67"],
       label = ['10', '200', '50', '100', '5', '500', '0', "jPOT"],
       slices = color.length,
       sliceDeg = 360/slices,
       deg = rand(0, 360),
       speed = 0,
       slowDownRand = 0,
       ctx = canvas.getContext('2d'),
       width = canvas.width,
       center = width/2,
       isStopped = false,
       lock = false;

    deg2rad(deg): your-return-type2 {
      return deg * Math.PI/180;
    }