How to output triangles in javascript: first write a static canvas container; then use js to get the container with the id canvas, and define it as a canvas; finally use js to draw the triangle.
The operating environment of this article: Windows 7 system, JavaScript version 1.8.5, Dell G3 computer.
First step, open the sublimeText editor, as shown below
Second step, write a static canvas container, the example is a 300x300 container, details The code is as shown below
The third step is to use js to get the container with the id canvas, and then define it as a canvas
//获取canvas容器 var canvas = document.getElementById('canvas'); //创建一个画布 var huabu = canvas.getContext('2d');
, the detailed code is as follows Figure
The fourth step is to draw a triangle using js [Recommended learning: js basic tutorial]
Example code: Draw 3 Use three coordinate points of a triangle to draw a line
//获取canvas容器 var canvas = document.getElementById('canvas'); //创建一个画布 var huabu = canvas.getContext('2d'); // 开始绘制 huabu.beginPath(); // 从画布坐标(50,50)开始绘画 huabu.moveTo(50,50); // 三角形第二个坐标点(200,50) huabu.lineTo(200,50); // 三角形第二个坐标点(125,100) huabu.lineTo(125,100); //自动闭合 huabu.closePath(); huabu.stroke();
The detailed code is as shown below. ,
The fifth step, the triangle effect drawn by js, as shown below
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