一、App平台支付流程

流程:支付平台功能申请 -> manifest.json 里配置支付参数 -> uni-app 里调用 API 进行支付

二、微信App支付功能申请

  1. 微信开放平台 申请移动应用并开通支付功能,申请应用后可以获取 AppIDAppSecret
  2. 应用接入 微信商户平台,选择 App 支付
  3. 开通支付功能后可获取支付业务服务器配置数据:PARTNER(财付通商户号)、PARTNER_KEY(财付通密钥)、PAYSIGNKEY(支付签名密钥)
  4. 需要将从微信开放平台申请的appid,填回到 manifest-App SDK配置-支付-微信支付 中。打包后生效
//微信支付
uni.getProvider({
    service: 'payment',		//获取服务供应商
    success: (res)=> {
        console.log(res.service)	//服务类型:payment
		console.log(res.provider)	//不同服务类型下可能的取值:["alipay","wxpay"]
		// if(res.provider.indexOf('wxpay')){
			//服务提供商(从服务供应商中获取,是否包含微信支付)
			//调取后台接口,获取微信支付的订单号
			this.$Z.post(this.$url+'/UserOrderNumber',{
				你要传给后台的参数(具体看后台要什么参数)
			},{}).then(res=>{
				console.log('获取微信支付的订单号',res)
				let orderData = res.data.orderNumber
				//调取后台接口,获取微信支付的订单数据
				this.$Z.post(this.$url+'/pay/aliPay',{
					//把订单号与支付方式传给后台(具体看后台要什么参数)
				},{}).then(res=>{
					let weixinOrderInfo = res.data.data;	从后台返回的微信订单数据
					let weixinorder = this.getPayInfo(weixinOrderInfo);
					//支付
					uni.requestPayment({
						provider: 'wxpay',	//服务提供商(微信)(服务提供商,通过uni.getProvider获取)
						orderInfo:weixinorder,
						success(res){
							console.log('success:' + JSON.stringify(res));
						},
						fail(err){
							console.log('fail:' + JSON.stringify(err));
						}
					});
				})
			})
		// }
    }
});



//二次签名
getPayInfo (orderInfo) {
	let res = orderInfo, // 后台返回的统一下单数据
		key = "", // 加密Key,微信支付填写的key(后台提供)
		payInfo = {
			appid: res.appid,
			noncestr:res.noncestr,
			package: res.package,
			partnerid: res.partnerid,
			prepayid: res.prepayid,
			timestamp: Number(res.timestamp),
	}
	// 键值对按照ASCII码从小到大排序生成类似:appid=xxx&body=xx&device_info=1000
	let keyValueStr = this.mapObjToKeyValue(payInfo, true);
	// 插入加密Key到最后
	let strSignTemp = `${keyValueStr}&key=${key}`;
	// 真正的二次加密(需要引入md5.js源码,小编文章最后会附)
	let sign = md5(strSignTemp).toUpperCase().substr(0, 32);	
	console.log(sign) // 可以去微信支付文档做校验
	payInfo.sign = sign;
	// 返回字符串给uniapp调起支付用
	return JSON.stringify(payInfo);
},
/*
 * 根据object生成key value字符串
 * @params obj: any 要map的对象
 * @params isSort: boolean 是否根据ASCII字典排序
 */
mapObjToKeyValue(obj, isSort = false) {
	let keys = Object.keys(obj);
	let str = "";
	
	if (isSort) keys.sort();
	keys.forEach(key => {
		if (obj.hasOwnProperty(key)) {
			str += `${key}=${obj[key]}&`;
		}
	});
	return str.replace(/&$/, "");
},

后台返回的微信订单参数:参照微信支付文档的统一下单参数进行对比

如在其过程中遇到:

uniapp APP端微信支付 签名错误,是因为uniapp调起微信支付需要进行第二次签名的,即根据后端统一下单返回数据再进行一次签名,签名方式要确保一致。详情请参照uniapp APP端微信支付 签名错误

附:md5.js源码
/*
 * JavaScript MD5
 * https://github.com/blueimp/JavaScript-MD5
 *
 * Copyright 2011, Sebastian Tschan
 * https://blueimp.net
 *
 * Licensed under the MIT license:
 * https://opensource.org/licenses/MIT
 *
 * Based on
 * A JavaScript implementation of the RSA Data Security, Inc. MD5 Message
 * Digest Algorithm, as defined in RFC 1321.
 * Version 2.2 Copyright (C) Paul Johnston 1999 - 2009
 * Other contributors: Greg Holt, Andrew Kepert, Ydnar, Lostinet
 * Distributed under the BSD License
 * See http://pajhome.org.uk/crypt/md5 for more info.
 */

/* global define */

;(function ($) {
  'use strict'

  /*
  * Add integers, wrapping at 2^32. This uses 16-bit operations internally
  * to work around bugs in some JS interpreters.
  */
  function safeAdd (x, y) {
    var lsw = (x & 0xffff) + (y & 0xffff)
    var msw = (x >> 16) + (y >> 16) + (lsw >> 16)
    return (msw << 16) | (lsw & 0xffff)
  }

  /*
  * Bitwise rotate a 32-bit number to the left.
  */
  function bitRotateLeft (num, cnt) {
    return (num << cnt) | (num >>> (32 - cnt))
  }

  /*
  * These functions implement the four basic operations the algorithm uses.
  */
  function md5cmn (q, a, b, x, s, t) {
    return safeAdd(bitRotateLeft(safeAdd(safeAdd(a, q), safeAdd(x, t)), s), b)
  }
  function md5ff (a, b, c, d, x, s, t) {
    return md5cmn((b & c) | (~b & d), a, b, x, s, t)
  }
  function md5gg (a, b, c, d, x, s, t) {
    return md5cmn((b & d) | (c & ~d), a, b, x, s, t)
  }
  function md5hh (a, b, c, d, x, s, t) {
    return md5cmn(b ^ c ^ d, a, b, x, s, t)
  }
  function md5ii (a, b, c, d, x, s, t) {
    return md5cmn(c ^ (b | ~d), a, b, x, s, t)
  }

  /*
  * Calculate the MD5 of an array of little-endian words, and a bit length.
  */
  function binlMD5 (x, len) {
    /* append padding */
    x[len >> 5] |= 0x80 << (len % 32)
    x[((len + 64) >>> 9 << 4) + 14] = len

    var i
    var olda
    var oldb
    var oldc
    var oldd
    var a = 1732584193
    var b = -271733879
    var c = -1732584194
    var d = 271733878

    for (i = 0; i < x.length; i += 16) {
      olda = a
      oldb = b
      oldc = c
      oldd = d

      a = md5ff(a, b, c, d, x[i], 7, -680876936)
      d = md5ff(d, a, b, c, x[i + 1], 12, -389564586)
      c = md5ff(c, d, a, b, x[i + 2], 17, 606105819)
      b = md5ff(b, c, d, a, x[i + 3], 22, -1044525330)
      a = md5ff(a, b, c, d, x[i + 4], 7, -176418897)
      d = md5ff(d, a, b, c, x[i + 5], 12, 1200080426)
      c = md5ff(c, d, a, b, x[i + 6], 17, -1473231341)
      b = md5ff(b, c, d, a, x[i + 7], 22, -45705983)
      a = md5ff(a, b, c, d, x[i + 8], 7, 1770035416)
      d = md5ff(d, a, b, c, x[i + 9], 12, -1958414417)
      c = md5ff(c, d, a, b, x[i + 10], 17, -42063)
      b = md5ff(b, c, d, a, x[i + 11], 22, -1990404162)
      a = md5ff(a, b, c, d, x[i + 12], 7, 1804603682)
      d = md5ff(d, a, b, c, x[i + 13], 12, -40341101)
      c = md5ff(c, d, a, b, x[i + 14], 17, -1502002290)
      b = md5ff(b, c, d, a, x[i + 15], 22, 1236535329)

      a = md5gg(a, b, c, d, x[i + 1], 5, -165796510)
      d = md5gg(d, a, b, c, x[i + 6], 9, -1069501632)
      c = md5gg(c, d, a, b, x[i + 11], 14, 643717713)
      b = md5gg(b, c, d, a, x[i], 20, -373897302)
      a = md5gg(a, b, c, d, x[i + 5], 5, -701558691)
      d = md5gg(d, a, b, c, x[i + 10], 9, 38016083)
      c = md5gg(c, d, a, b, x[i + 15], 14, -660478335)
      b = md5gg(b, c, d, a, x[i + 4], 20, -405537848)
      a = md5gg(a, b, c, d, x[i + 9], 5, 568446438)
      d = md5gg(d, a, b, c, x[i + 14], 9, -1019803690)
      c = md5gg(c, d, a, b, x[i + 3], 14, -187363961)
      b = md5gg(b, c, d, a, x[i + 8], 20, 1163531501)
      a = md5gg(a, b, c, d, x[i + 13], 5, -1444681467)
      d = md5gg(d, a, b, c, x[i + 2], 9, -51403784)
      c = md5gg(c, d, a, b, x[i + 7], 14, 1735328473)
      b = md5gg(b, c, d, a, x[i + 12], 20, -1926607734)

      a = md5hh(a, b, c, d, x[i + 5], 4, -378558)
      d = md5hh(d, a, b, c, x[i + 8], 11, -2022574463)
      c = md5hh(c, d, a, b, x[i + 11], 16, 1839030562)
      b = md5hh(b, c, d, a, x[i + 14], 23, -35309556)
      a = md5hh(a, b, c, d, x[i + 1], 4, -1530992060)
      d = md5hh(d, a, b, c, x[i + 4], 11, 1272893353)
      c = md5hh(c, d, a, b, x[i + 7], 16, -155497632)
      b = md5hh(b, c, d, a, x[i + 10], 23, -1094730640)
      a = md5hh(a, b, c, d, x[i + 13], 4, 681279174)
      d = md5hh(d, a, b, c, x[i], 11, -358537222)
      c = md5hh(c, d, a, b, x[i + 3], 16, -722521979)
      b = md5hh(b, c, d, a, x[i + 6], 23, 76029189)
      a = md5hh(a, b, c, d, x[i + 9], 4, -640364487)
      d = md5hh(d, a, b, c, x[i + 12], 11, -421815835)
      c = md5hh(c, d, a, b, x[i + 15], 16, 530742520)
      b = md5hh(b, c, d, a, x[i + 2], 23, -995338651)

      a = md5ii(a, b, c, d, x[i], 6, -198630844)
      d = md5ii(d, a, b, c, x[i + 7], 10, 1126891415)
      c = md5ii(c, d, a, b, x[i + 14], 15, -1416354905)
      b = md5ii(b, c, d, a, x[i + 5], 21, -57434055)
      a = md5ii(a, b, c, d, x[i + 12], 6, 1700485571)
      d = md5ii(d, a, b, c, x[i + 3], 10, -1894986606)
      c = md5ii(c, d, a, b, x[i + 10], 15, -1051523)
      b = md5ii(b, c, d, a, x[i + 1], 21, -2054922799)
      a = md5ii(a, b, c, d, x[i + 8], 6, 1873313359)
      d = md5ii(d, a, b, c, x[i + 15], 10, -30611744)
      c = md5ii(c, d, a, b, x[i + 6], 15, -1560198380)
      b = md5ii(b, c, d, a, x[i + 13], 21, 1309151649)
      a = md5ii(a, b, c, d, x[i + 4], 6, -145523070)
      d = md5ii(d, a, b, c, x[i + 11], 10, -1120210379)
      c = md5ii(c, d, a, b, x[i + 2], 15, 718787259)
      b = md5ii(b, c, d, a, x[i + 9], 21, -343485551)

      a = safeAdd(a, olda)
      b = safeAdd(b, oldb)
      c = safeAdd(c, oldc)
      d = safeAdd(d, oldd)
    }
    return [a, b, c, d]
  }

  /*
  * Convert an array of little-endian words to a string
  */
  function binl2rstr (input) {
    var i
    var output = ''
    var length32 = input.length * 32
    for (i = 0; i < length32; i += 8) {
      output += String.fromCharCode((input[i >> 5] >>> (i % 32)) & 0xff)
    }
    return output
  }

  /*
  * Convert a raw string to an array of little-endian words
  * Characters >255 have their high-byte silently ignored.
  */
  function rstr2binl (input) {
    var i
    var output = []
    output[(input.length >> 2) - 1] = undefined
    for (i = 0; i < output.length; i += 1) {
      output[i] = 0
    }
    var length8 = input.length * 8
    for (i = 0; i < length8; i += 8) {
      output[i >> 5] |= (input.charCodeAt(i / 8) & 0xff) << (i % 32)
    }
    return output
  }

  /*
  * Calculate the MD5 of a raw string
  */
  function rstrMD5 (s) {
    return binl2rstr(binlMD5(rstr2binl(s), s.length * 8))
  }

  /*
  * Calculate the HMAC-MD5, of a key and some data (raw strings)
  */
  function rstrHMACMD5 (key, data) {
    var i
    var bkey = rstr2binl(key)
    var ipad = []
    var opad = []
    var hash
    ipad[15] = opad[15] = undefined
    if (bkey.length > 16) {
      bkey = binlMD5(bkey, key.length * 8)
    }
    for (i = 0; i < 16; i += 1) {
      ipad[i] = bkey[i] ^ 0x36363636
      opad[i] = bkey[i] ^ 0x5c5c5c5c
    }
    hash = binlMD5(ipad.concat(rstr2binl(data)), 512 + data.length * 8)
    return binl2rstr(binlMD5(opad.concat(hash), 512 + 128))
  }

  /*
  * Convert a raw string to a hex string
  */
  function rstr2hex (input) {
    var hexTab = '0123456789abcdef'
    var output = ''
    var x
    var i
    for (i = 0; i < input.length; i += 1) {
      x = input.charCodeAt(i)
      output += hexTab.charAt((x >>> 4) & 0x0f) + hexTab.charAt(x & 0x0f)
    }
    return output
  }

  /*
  * Encode a string as utf-8
  */
  function str2rstrUTF8 (input) {
    return unescape(encodeURIComponent(input))
  }

  /*
  * Take string arguments and return either raw or hex encoded strings
  */
  function rawMD5 (s) {
    return rstrMD5(str2rstrUTF8(s))
  }
  function hexMD5 (s) {
    return rstr2hex(rawMD5(s))
  }
  function rawHMACMD5 (k, d) {
    return rstrHMACMD5(str2rstrUTF8(k), str2rstrUTF8(d))
  }
  function hexHMACMD5 (k, d) {
    return rstr2hex(rawHMACMD5(k, d))
  }

  function md5 (string, key, raw) {
    if (!key) {
      if (!raw) {
        return hexMD5(string)
      }
      return rawMD5(string)
    }
    if (!raw) {
      return hexHMACMD5(key, string)
    }
    return rawHMACMD5(key, string)
  }

  if (typeof define === 'function' && define.amd) {
    define(function () {
      return md5
    })
  } else if (typeof module === 'object' && module.exports) {
    module.exports = md5
  } else {
    $.md5 = md5
  }
})(this)