wxml

<button wx:else class="bindMobile" open-type="getPhoneNumber" bindgetphonenumber="bindMobile">绑定手机号</button>

js

async bindMobile(e){
	if (e.detail.errMsg === 'getPhoneNumber:ok') {
		const code = e.detail.code; 
		const openid = wx.getStorageSync('openid');
		const data =  await api.bindMobile({code:code,openid:openid},true);
		if(data.code == 1){
			wx.showToast({
				title: '绑定成功',
				icon: 'success',
			})
			this.getUserInfo();
		}
	} else {
		console.log('用户拒绝授权');
	}
},

php

//绑定用户手机号
public function bindMobile(){
	$input = safeInput('post.');
	$openid = $input['openid'];
	$code = $input['code'];

	$url = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=".env('XCX.appid')."&secret=".env('XCX.secret');
	$res = file_get_contents($url);
	$res = json_decode($res, true);
	$token= $res['access_token'];
	$data = json_encode(['code' => $code]);
	$url = "https://api.weixin.qq.com/wxa/business/getuserphonenumber?access_token=".$token;
	$response = json_decode(file_get_contents($url, false, stream_context_create([
		'http' => [
			'method' => 'POST',
			'header' => 'Content-Type: application/json',
			'content' => $data
		]
	])), true);
	
	if($response['errcode'] !== 0) {
		return json(['code'=>0,'msg'=>'绑定失败','autoMsg'=>'alert']);
	}

	$mobile = $response['phone_info']['phoneNumber'];

	Db::name('user_snslogin')->where('openid',$openid)->update(['mobile'=>$mobile]);
	return json(['code'=>1,'msg'=>'绑定成功']);
}