1、php服务器生成图片验证码的代码片段如下：

注意红框部分的代码，生成的是ArrayBuffer类型的二进制图片

2、显示验证码

显示验证码，不要直接image组件加上src显示，那样拿不到cookie，没有办法做图形验证码的验证，需要通过接口的方法获取，上接口代码如下：

function get_verify_code(url, success, fail, complete) {if (request_status == true) {return;}request_status = true;let header = {'Content-Type': 'application/x-www-form-urlencoded'};uni.request({url: url,timeout: 60000,header: header,responseType: 'arraybuffer',//这个地方不要写错method: 'GET',success: res => {request_status = false;if (res.statusCode == 200) {let cookieKey = '';let data = res.data;//拿的图片// #ifdef MP-WEIXINif (res && res.header && res.header['Set-Cookie']) {cookieKey = res.header['Set-Cookie'];//拿cookie}// #endifsuccess({"data":data,"cookieKey":cookieKey});} else if (res.statusCode == 404) {success({"success": false,"field": "fail_net","message": "请求的资源不存在"});} else if (res.statusCode == 500) {success({"success": false,"field": "fail_net","message": "内部服务器错误"});} else {success({"success": false,"field": "fail_net","message": "请求异常"});}},fail: (e) => {if (request_status == true) {request_status = false;}fail(e);},complete: (e) => {if (request_status == true) {request_status = false;}complete(e);}});
}

显示图片的操作代码如下：

get_verify_code(v) {let url = `${base_url}get_verify_code/${v}`;//console.log('url:'+url);this.$net.get_verify_code(url,res => {const base64 = uni.arrayBufferToBase64(res.data);this.imageData  = `data:image/png;base64,${base64}`;// #ifdef MP-WEIXINif (res.cookieKey) {uni.setStorageSync('cookieKey', res.cookieKey);}// #endif},() => {},() => {});},

这样图片就可以正常显示了，提交的方法里要带上cookie，这样就可以验证验证码了。