1. 程式人生 > >vue系列---identify(生成圖片驗證碼)外掛

vue系列---identify(生成圖片驗證碼)外掛

export default{ name: 'SIdentify', props: { identifyCode: { type: String, default: '1234' }, fontSizeMin: { type: Number, default: 16 }, fontSizeMax: { type: Number, default: 40 }, backgroundColorMin: { type: Number
, default: 180 }, backgroundColorMax: { type: Number, default: 240 }, colorMin: { type: Number, default: 50 }, colorMax: { type: Number, default: 160 }, lineColorMin: { type: Number, default
: 40 }, lineColorMax: { type: Number, default: 180 }, dotColorMin: { type: Number, default: 0 }, dotColorMax: { type: Number, default: 255 }, contentWidth: { type: Number, default: 112 }, contentHeight: { type: Number
, default: 38 } }, methods: { // 生成一個隨機數 randomNum (min, max) { return Math.floor(Math.random() * (max - min) + min) }, // 生成一個隨機的顏色 randomColor (min, max) { let r = this.randomNum(min, max) let g = this.randomNum(min, max) let b = this.randomNum(min, max) return 'rgb(' + r + ',' + g + ',' + b + ')' }, drawPic () { let canvas = document.getElementById('s-canvas') let ctx = canvas.getContext('2d') ctx.textBaseline = 'bottom' // 繪製背景 ctx.fillStyle = this.randomColor(this.backgroundColorMin, this.backgroundColorMax) ctx.fillRect(0, 0, this.contentWidth, this.contentHeight) // 繪製文字 for (let i = 0; i < this.identifyCode.length; i++) { this.drawText(ctx, this.identifyCode[i], i) } this.drawLine(ctx) this.drawDot(ctx) }, drawText (ctx, txt, i) { ctx.fillStyle = this.randomColor(this.colorMin, this.colorMax) ctx.font = this.randomNum(this.fontSizeMin, this.fontSizeMax) + 'px SimHei' let x = (i + 1) * (this.contentWidth / (this.identifyCode.length + 1)) let y = this.randomNum(this.fontSizeMax, this.contentHeight - 5) var deg = this.randomNum(-45, 45) // 修改座標原點和旋轉角度 ctx.translate(x, y) ctx.rotate(deg * Math.PI / 180) ctx.fillText(txt, 0, 0) // 恢復座標原點和旋轉角度 ctx.rotate(-deg * Math.PI / 180) ctx.translate(-x, -y) }, drawLine (ctx) { // 繪製干擾線 for (let i = 0; i < 8; i++) { ctx.strokeStyle = this.randomColor(this.lineColorMin, this.lineColorMax) ctx.beginPath() ctx.moveTo(this.randomNum(0, this.contentWidth), this.randomNum(0, this.contentHeight)) ctx.lineTo(this.randomNum(0, this.contentWidth), this.randomNum(0, this.contentHeight)) ctx.stroke() } }, drawDot (ctx) { // 繪製干擾點 for (let i = 0; i < 100; i++) { ctx.fillStyle = this.randomColor(0, 255) ctx.beginPath() ctx.arc(this.randomNum(0, this.contentWidth), this.randomNum(0, this.contentHeight), 1, 0, 2 * Math.PI) ctx.fill() } } }, watch: { identifyCode () { this.drawPic() } }, mounted () { this.drawPic() } }