开发者技术支持-微信登录

# 问题说明

进行第三方微信登录时，需要获取先拿到微信返回的code，然后使用code获取到对应的登录token，完成微信登录

## 获取Code

import * as wxopensdk from '@tencent/wechat_open_sdk';
import { APP_ID } from '../Constants';

export type OnWXReq = (req: wxopensdk.BaseReq) => void
export type OnWXResp = (resp: wxopensdk.BaseResp) => void

const kTag = "WXApiEventHandlerImpl"

class WXApiEventHandlerImpl implements wxopensdk.WXApiEventHandler {
 private onReqCallbacks: Map<OnWXReq, OnWXReq> = new Map
 private onRespCallbacks: Map<OnWXResp, OnWXResp> = new Map

 registerOnWXReqCallback(on: OnWXReq) {
   this.onReqCallbacks.set(on, on)
 }
 unregisterOnWXReqCallback(on: OnWXReq) {
   this.onReqCallbacks.delete(on)
 }

 registerOnWXRespCallback(on: OnWXResp) {
   this.onRespCallbacks.set(on, on)
 }
 unregisterOnWXRespCallback(on: OnWXResp) {
   this.onRespCallbacks.delete(on)
 }

 onReq(req: wxopensdk.BaseReq): void {
   wxopensdk.Log.i(kTag, "onReq:%s", JSON.stringify(req))
   this.onReqCallbacks.forEach((on) => {
     on(req)
   })
 }

 onResp(resp: wxopensdk.BaseResp): void {
   wxopensdk.Log.i(kTag, "onResp:%s", JSON.stringify(resp))
   this.onRespCallbacks.forEach((on) => {
     on(resp)
   })
 }
}

export const WXApi = wxopensdk.WXAPIFactory.createWXAPI(APP_ID)
export const WXEventHandler = new WXApiEventHandlerImpl

将上面的代码全部复制到项目中去即可，在需要进行登录的事件中，填入下面的代码，用于向微信发送请求获取code。

let req = new wxopensdk.SendAuthReq
        req.isOption1 = false
        req.nonAutomatic = true
        req.scope = 'snsapi_userinfo,snsapi_friend,snsapi_message,snsapi_contact'
        req.state = 'none'
        req.transaction = 'test123'

        await this.wxApi.sendReq(getContext(this) as common.UIAbilityContext, req)

完成后，还需要获取到微信返回的code值，在EntryAbility文件中，示例代码如下：

export default class EntryAbility extends UIAbility {
  onCreate(want: Want, _launchParam: AbilityConstant.LaunchParam): void {
    this.handleWeChatCallIfNeed(want)
  }

  onNewWant(want: Want, _launchParam: AbilityConstant.LaunchParam): void {
    this.handleWeChatCallIfNeed(want)
  }

  private handleWeChatCallIfNeed(want: Want) {
    WXApi.handleWant(want, WXEventHandler)
  }
}

获取到code以后，就可以向微信发送请求，获取token。