node.js图形验证码

• captchapng 原始的地址 captchapng.
• captchapng2 原始的地址 captchapng.
• 基于 captchapng2 增加了背景色和前景色的方法。
• new captchapng 方法传入宽，高，验证码，背景色，前景色
• 前景色的RGBA，透明度取值范围是0-255

安装说明

npm install captchapng3
yarn add captchapng3

JS示例

const http = require('http');
const captchapng = require('captchapng3');

http.createServer(function (req, res) {
  if(req.url == '/captcha.png') {
		const code = `0000${parseInt(Math.random() * 10000)}`.substr(-4);
    const png = new captchapng(80, 35, code, '#cfb988', [
			[11, 5, 73, 107],
			[15, 56, 123, 245],
			[88, 28, 130, 144],
			[230, 74, 79, 198],
			[67, 236, 243, 112],
			[166, 44, 215, 114]
		]);
		// captchapng2的方法
		// const png = new captchapng(80, 35, code);
    res.writeHead(200, { 'Content-Type': 'image/png'});
    res.end(png.getBuffer());
  } else {
    res.end('');
  }
}).listen(8181);

console.log('Web server started.\nSee http:\\\\127.0.0.1:8181\\captcha.png');

egg.js示例

egg.js

const Controller = require('egg').Controller;
const captchapng = require('captchapng3');
class SubmitController extends Controller {
	async picture() {
		const {
			ctx
		} = this;
		// 生成四位纯数字的验证码
		const code = `0000${parseInt(Math.random() * 10000)}`.substr(-4);
		ctx.session.messageCode = code;
		const png = new captchapng(80, 35, code, '#cfb988', [
			[11, 5, 73, 107],
			[15, 56, 123, 245],
			[88, 28, 130, 144],
			[230, 74, 79, 198],
			[67, 236, 243, 112],
			[166, 44, 215, 114]
		]);
		// captchapng2的方法
		// const png = new captchapng(80, 35, code);
		ctx.type = 'image/png';
		ctx.body = png.getBuffer();
	}
}


module.exports = SubmitController;