微信小程序环境下将文件上传到OSS的方法步骤

accessid= '';accesskey= '';host = '';g_dirname = ''g_object_name = ''g_object_name_type = ''now = timestamp = Date.parse(new Date()) / 1000; var policyText = {  "expiration": "2020-01-01T12:00:00.000Z", //设置该Policy的失效时间，超过这个失效时间之后，就没有办法通过这个policy上传文件了  "conditions": [  ["content-length-range", 0, 1048576000] // 设置上传文件的大小限制  ]};var policyBase64 = Base64.encode(JSON.stringify(policyText))message = policyBase64var bytes = Crypto.HMAC(Crypto.SHA1, message, accesskey, { asBytes: true }) ;var signature = Crypto.util.bytesToBase64(bytes);function check_object_radio() {  var tt = document.getElementsByName('myradio');  for (var i = 0; i < tt.length ; i++ )  {    if(tt[i].checked)    {      g_object_name_type = tt[i].value;      break;    }  }}function get_dirname(){  dir = document.getElementById("dirname").value;  if (dir != '' && dir.indexOf('/') != dir.length - 1)  {    dir = dir + '/'  }  //alert(dir)  g_dirname = dir}function random_string(len) {　　len = len || 32;　　var chars = 'ABCDEFGHJKMNPQRSTWXYZabcdefhijkmnprstwxyz2345678';  　　var maxPos = chars.length;　　var pwd = '';　　for (i = 0; i < len; i++) {  　　pwd += chars.charAt(Math.floor(Math.random() * maxPos));  }  return pwd;}function get_suffix(filename) {  pos = filename.lastIndexOf('.')  suffix = ''  if (pos != -1) {    suffix = filename.substring(pos)  }  return suffix;}function calculate_object_name(filename){  if (g_object_name_type == 'local_name')  {    g_object_name += "${filename}"  }  else if (g_object_name_type == 'random_name')  {    suffix = get_suffix(filename)    g_object_name = g_dirname + random_string(10) + suffix  }  return ''}function get_uploaded_object_name(filename){  if (g_object_name_type == 'local_name')  {    tmp_name = g_object_name    tmp_name = tmp_name.replace("${filename}", filename);    return tmp_name  }  else if(g_object_name_type == 'random_name')  {    return g_object_name  }}function set_upload_param(up, filename, ret){  g_object_name = g_dirname;  if (filename != '') {    suffix = get_suffix(filename)    calculate_object_name(filename)  }  new_multipart_params = {    'key' : g_object_name,    'policy': policyBase64,    'OSSAccessKeyId': accessid,     'success_action_status' : '200', //让服务端返回200,不然，默认会返回204    'signature': signature,  };  up.setOption({    'url': host,    'multipart_params': new_multipart_params  });  up.start();}var uploader = new plupload.Uploader({  runtimes : 'html5,flash,silverlight,html4',  browse_button : 'selectfiles',   //multi_selection: false,  container: document.getElementById('container'),  flash_swf_url : 'lib/plupload-2.1.2/js/Moxie.swf',  silverlight_xap_url : 'lib/plupload-2.1.2/js/Moxie.xap',  url : 'http://oss.aliyuncs.com',  init: {    PostInit: function() {      document.getElementById('ossfile').innerHTML = '';      document.getElementById('postfiles').onclick = function() {      set_upload_param(uploader, '', false);      return false;      };    },    FilesAdded: function(up, files) {      plupload.each(files, function(file) {        document.getElementById('ossfile').innerHTML += '<div id="' + file.id + '">' + file.name + ' (' + plupload.formatSize(file.size) + ')<b></b>'        +'<div class="progress"><div class="progress-bar" style="width: 0%"></div></div>'        +'</div>';      });    },    BeforeUpload: function(up, file) {      check_object_radio();      get_dirname();      set_upload_param(up, file.name, true);    },    UploadProgress: function(up, file) {      var d = document.getElementById(file.id);      d.getElementsByTagName('b')[0].innerHTML = '<span>' + file.percent + "%</span>";      var prog = d.getElementsByTagName('div')[0];      var progBar = prog.getElementsByTagName('div')[0]      progBar.style.width= 2*file.percent+'px';      progBar.setAttribute('aria-valuenow', file.percent);    },    FileUploaded: function(up, file, info) {      if (info.status == 200)      {        document.getElementById(file.id).getElementsByTagName('b')[0].innerHTML = 'upload to oss success, object name:' + get_uploaded_object_name(file.name);      }      else      {        document.getElementById(file.id).getElementsByTagName('b')[0].innerHTML = info.response;      }     },    Error: function(up, err) {      document.getElementById('console').appendChild(document.createTextNode("/nError xml:" + err.response));    }  }});uploader.init();

<!DOCTYPE html><html><head>  <meta http-equiv="content-type" content="text/html; charset=UTF-8"/>  <title>OSS web直传</title>  <link rel="stylesheet" type="text/css" href="style.css"/>  <meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, user-scalable=no"></head><body><h2>OSS web直传---直接在JS签名</h2><ol><li>基于plupload封装 </li><li>支持html5,flash,silverlight,html4 等协议上传</li><li>可以运行在PC浏览器，手机浏览器，微信</li><li>可以选择多文件上传</li><li>显示上传进度条</li><li>可以控制上传文件的大小</li><li>最关键的是，让你10分钟之内就能移植到你的系统，实现以上牛逼的功能！</li><li>注意一点，bucket必须设置了Cors(Post打勾）,不然没有办法上传</li><li>注意一点，把upload.js 里面的host/accessid/accesskey改成您上传所需要的信息即可</li><li>此方法是直接在前端签名，有accessid/accesskey泄漏的风险, 线上生产请使用后端签名例子<a href="https://help.aliyun.com/document_detail/oss/practice/pc_web_upload/js_php_upload.html">点击查看详细文档</a></li></ol><br><form name=theform><input type="radio" name="myradio" value="local_name" checked=true/> 上传文件名字保持本地文件名字<input type="radio" name="myradio" value="random_name" /> 上传文件名字是随机文件名<br/>上传到指定目录:<input type="text" id='dirname' placeholder="如果不填，默认是上传到根目录" size=50></form><h4>您所选择的文件列表：</h4><div id="ossfile">你的浏览器不支持flash,Silverlight或者HTML5！</div><br/><div id="container">  <a id="selectfiles" href="javascript:void(0);" class='btn'>选择文件</a>  <a id="postfiles" href="javascript:void(0);" class='btn'>开始上传</a></div><pre id="console"></pre><p> </p></body><script type="text/javascript" src="lib/crypto1/crypto/crypto.js"></script><script type="text/javascript" src="lib/crypto1/hmac/hmac.js"></script><script type="text/javascript" src="lib/crypto1/sha1/sha1.js"></script><script type="text/javascript" src="lib/base64.js"></script><script type="text/javascript" src="lib/plupload-2.1.2/js/plupload.full.min.js"></script><script type="text/javascript" src="upload.js"></script></html>

this.$navigate({url:"content"})this.$parent.$navigate({url:"content"})wepy.navigateTo({url: '/pages/content'})