按照惯例，先是官方传送门：https://developers.weixin.qq.com/miniprogram/dev/api/api-login.html
1.登录流程介绍
调用微信开放接口wx.login获取一个临时的登录凭证code
微信小程序通过https请求访问自己的服务器，服务器携带登录凭证code以及小程序的appid和appsecret从微信服务器中获取openid和session_key，UnionID 只在满足一定条件的情况下返回，另外，一个code只能使用一次。
2.开发
2.1 前端
wxml：
< button class= "login" type= "" open-type= "getUserInfo" bindgetuserinfo= "login">微信登录 </ button >
wxss：（目的是为了去除微信button自带的样式）
.login{ background-color: #FFF; box-sizing: unset; } .login::after{ border: 0 rpx; }
感受一下加了这段css的前后变化
js：
login: function (e) { var that = this; //调用登录接口，获取 code if (wx.getStorageSync( "userInfo") && wx.getStorageSync( "empInfo")){ return; } wx.login({ success: function (res) { wx.getSetting({ success(setRes) { // 判断是否已授权 if (!setRes.authSetting[ 'scope.userInfo']) { // 授权访问 wx.authorize({ scope: 'scope.userInfo', success() { //获取用户信息 wx.getUserInfo({ lang: "zh_CN", success: function (userRes) { //发起网络请求 wx.request({ //url: API_URL, url: address+ 'getWxUserInfo', data: { grant_type: "authorization_code", encryptedData: userRes.encryptedData, iv: userRes.iv, code: res.code }, header: { "Content-Type": "application/x-www-form-urlencoded" }, method: 'POST', //服务端的回掉 success: function (result) { var openid = result.data.openid; var session_key = result.data.session_key that.data.userInfo.openid = openid; that.data.userInfo.session_key = session_key; wx.setStorageSync( "userInfo", that.data.userInfo); that.showModal(); }, fail: function () { wx.showToast({ title: '服务器异常，清稍候再试', icon: 'none' }) } }) }, }) } }) } else { //获取用户信息 wx.getUserInfo({ lang: "zh_CN", success: function (userRes) { that.setData({ userInfo: userRes.userInfo }) //发起网络请求 wx.request({ url: address + 'getWxUserInfo' , data: { grant_type: "authorization_code", encryptedData: userRes.encryptedData, iv: userRes.iv, code: res.code, }, header: { "Content-Type": "application/x-www-form-urlencoded" }, method: 'POST', success: function (result) { var openid = result.data.openid; var session_key = result.data.session_key that.data.userInfo.openid = openid; that.data.userInfo.session_key = session_key; wx.setStorageSync( "userInfo", that.data.userInfo); that.showModal(); }, fail: function () { wx.showToast({ title: '服务器异常，清稍候再试', icon: 'none' }) } }) } }) } } }) }, fail: function (res) { wx.showToast({ title: '获取授权信息失败', icon: 'none' }) } }) },
java后端：
https请求：
@RequestMapping("/getWxUserInfo")
public static JSONObject getSessionKeyOropenid(String grant_type,String code,String iv,String encryptedData){
//微信端登录code值
//String wxCode = code;
//ResourceBundle resource = ResourceBundle.getBundle("weixin"); //读取属性文件
//String requestUrl = resource.getString("url"); //请求地址 https://api.weixin.qq.com/sns/jscode2session
Map<String,String> requestUrlParam = new HashMap<String,String>();
requestUrlParam.put("appid", WXConst.appId); //开发者设置中的appId
requestUrlParam.put("secret", WXConst.appSecret); //开发者设置中的appSecret
requestUrlParam.put("js_code", code); //小程序调用wx.login返回的code
requestUrlParam.put("grant_type", grant_type); //默认参数
//发送post请求读取调用微信 https://api.weixin.qq.com/sns/jscode2session 接口获取openid用户唯一标识
JSONObject jsonObject = JSON.parseObject(UrlUtil.sendPost(WXConst.WxGetOpenIdUrl, requestUrlParam));
return jsonObject;
}
UrlUtil.java
private static Logger log = Logger.getLogger(UrlUtil.class);
public static String sendPost(String url, Map<String, ?> paramMap) {
PrintWriter out = null;
BufferedReader in = null;
String result = "";
String param = "";
Iterator<String> it = paramMap.keySet().iterator();
while (it.hasNext()) {
String key = it.next();
param += key + "=" + paramMap.get(key) + "&";
}
param = param.substring(0,param.length()-1);
try {
URL realUrl = new URL(url);
// 打开和URL之间的连接
URLConnection conn = realUrl.openConnection();
// 设置通用的请求属性
conn.setRequestProperty("accept", "*/*");
conn.setRequestProperty("connection", "Keep-Alive");
conn.setRequestProperty("Accept-Charset", "utf-8");
conn.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
// 发送POST请求必须设置如下两行
conn.setDoOutput(true);
conn.setDoInput(true);
// 获取URLConnection对象对应的输出流
out = new PrintWriter(conn.getOutputStream());
// 发送请求参数
out.print(param);
// flush输出流的缓冲
out.flush();
// 定义BufferedReader输入流来读取URL的响应
in = new BufferedReader(new InputStreamReader(conn.getInputStream(), "UTF-8"));
String line;
while ((line = in.readLine()) != null) {
result += line;
}
} catch (Exception e) {
log.error(e.getMessage(), e);
}
// 使用finally块来关闭输出流、输入流
finally {
try {
if (out != null) {
out.close();
}
if (in != null) {
in.close();
}
} catch (IOException ex) {
ex.printStackTrace();
}
}
return result;
}
WXConst.java
//微信小程序appid
public static String appId = "";
//微信小程序appsecret
public static String appSecret = "";
//获取微信Openid的请求地址
public static String WxGetOpenIdUrl = "https://api.weixin.qq.com/sns/jscode2session";
就这样就好啦~很简单呐！！！