vue中使用canvas绘图详解

<template lang="pug">
    div
    	// 规定矩形区域的宽和高
        <canvas id="myCanvas" width="500" height="300"></canvas>
</template>

<script>
export default {
    data() {
        return {}
    },
    mounted() {
        this.xianDuan()
    },
    methods: {
        xianDuan(){
            var canvas = document.getElementById("myCanvas");
            var ctx = canvas.getContext("2d");
            ctx.moveTo(0,0);      // moveTo(x,y) 定义线条开始坐标
            ctx.lineTo(200,100);  // lineTo(x,y) 定义线条结束坐标
            ctx.stroke();
        },
    }
}
</script>

mounted() {
	this.sanJiaoXing()
},
methods: {
    sanJiaoXing(){
        var canvas = document.getElementById('myCanvas');
        var ctx = canvas.getContext("2d");
        ctx.beginPath();
        ctx.moveTo(0, 0);
        ctx.lineTo(100, 200);
        ctx.lineTo(400, 200);
        ctx.lineTo(0, 0);
        ctx.stroke();     // 无填充色
    },
}

mounted() {
	this.sanJiaoXing()
},
methods: {
    sanJiaoXing(){
        var canvas = document.getElementById('myCanvas');
        var ctx = canvas.getContext("2d");
        ctx.beginPath();
        ctx.moveTo(0, 0);
        ctx.lineTo(100, 200);
        ctx.lineTo(400, 200);
        ctx.lineTo(0, 0);
        ctx.fill();     // 有填充色
    },
}

mounted() {
    this.yuan()
},
methods: {
    yuan() {
        var c=document.getElementById("myCanvas");
        var ctx=c.getContext("2d");
        ctx.beginPath();
        ctx.arc(95,50,40,0,2*Math.PI);    // Math.PI圆周率π = 3.14 = 180°
        ctx.stroke();
    },
}

mounted() {
    this.xiaoLian()
},
methods: {
    xiaoLian() {
        let canvas = document.getElementById('myCanvas');
        let ctx = canvas.getContext('2d');
        ctx.beginPath();
        ctx.arc(75, 75, 50, 0, Math.PI * 2, true); // 绘制
        ctx.moveTo(110, 75);
        ctx.arc(75, 75, 35, 0, Math.PI, false); // 口(顺时针)
        ctx.moveTo(65, 65);
        ctx.arc(60, 65, 5, 0, Math.PI * 2, true); // 左眼
        ctx.moveTo(95, 65);
        ctx.arc(90, 65, 5, 0, Math.PI * 2, true); // 右眼
        ctx.stroke();
    },
}

mounted() {
    this.ziTi()
},
methods: {
    ziTi() {
        let canvas = document.getElementById("myCanvas");
        let ctx = canvas.getContext("2d");
        ctx.font="30px Arial";       // 设置字体及大小
        ctx.fillText("Hello World 泥巴巴", 10, 150);    // 实心文字
        ctx.strokeText("Hello World 泥巴巴", 10, 180);  // 空心文字
    }
}

mounted() {
    this.jianBian()
},
methods: {
    jianBian() {
        let canvas = document.getElementById("myCanvas");
        let ctx = canvas.getContext("2d");
        var grd = ctx.createLinearGradient(0, 0, 200,0);  // 设置渐变
        grd.addColorStop(0,"red");   // 渐变起始颜色
        grd.addColorStop(1,"orange");   // 渐变结束色
        ctx.fillStyle = grd;         // 填充色
        ctx.fillRect(10,10,200,100); // (x,y,width,height) 矩形坐标和宽高
    }
}