最近做的項目中用到了angular下上傳圖片功能，在做的過程中遇到了許多問題，最終都得以解決
angular上傳時和普通上傳時過程差不多，只不過是要不一些東西轉化為angular的東西。
1.ng-file-select,指令angular是沒此功能的，其實也是轉化成了change事件，不多說，直接上代碼
angular.module('myApp').directive('ngFileSelect', [ '$parse', '$timeout', function($parse, $timeout) { return function(scope, elem, attr) { var fn = $parse(attr['ngFileSelect']); elem.bind('change', function(evt) { var files = [], fileList, i; fileList = evt.target.files; if (fileList != null) { for (i = 0; i < fileList.length; i++) { files.push(fileList.item(i)); } } $timeout(function() { fn(scope, { $files : files, $event : evt }); }); }); }; }])2.服務 上傳文件前預覽并壓縮圖片功能
//上傳文件預覽angular.module('myServers',[]) .factory('fileReader', ['$q', '$log', function($q, $log) { var dataURItoBlob = function(dataURI) { // convert base64/URLEncoded data component to raw binary data held in a string var byteString; if (dataURI.split(',')[0].indexOf('base64') >= 0) byteString = atob(dataURI.split(',')[1]); else byteString = unescape(dataURI.split(',')[1]); // separate out the mime component var mimeString = dataURI.split(',')[0].split(':')[1].split(';')[0]; // write the bytes of the string to a typed array var ia = new Uint8Array(byteString.length); for (var i = 0; i < byteString.length; i++) { ia[i] = byteString.charCodeAt(i); } return new Blob([ia], { type: mimeString }); }; var onLoad = function(reader, deferred, scope,file) { return function() { scope.$apply(function() { var img = new Image(); //前端壓縮圖片 img.onload = function(){ //resize the image using canvas var canvas = document.createElement("canvas"); var ctx = canvas.getContext("2d"); var width = img.width; var height = img.height; var MAX_WIDTH = width>2500 ? width/2 : 2500; var MAX_HEIGHT = height>2500 ? height/2 : 2500; if (width > height) { if (width > MAX_WIDTH) { height *= MAX_WIDTH / width; width = MAX_WIDTH; } } else { if (height > MAX_HEIGHT) { width *= MAX_HEIGHT / height; height = MAX_HEIGHT; } } canvas.width = width ; canvas.height = height; ctx.drawImage(img, 0, 0, width, height); var dataURL = canvas.toDataURL('image/jpeg', 1); var blob = dataURItoBlob(dataURL); if(blob.size > 2000 * 1024){ dataURL = canvas.toDataURL('image/jpeg', .2); }else if(blob.size > 1000 * 1024){ dataURL = canvas.toDataURL('image/jpeg', .5); }else{ dataURL = canvas.toDataURL('image/jpeg', .8); } blob = dataURItoBlob(dataURL); deferred.resolve(blob); } img.src = URL.createObjectURL(file); }); }; }; var onError = function(reader, deferred, scope) { return function() { scope.$apply(function() { deferred.reject(reader.result); }); }; }; var onProgress = function(reader, scope) { return function(event) { scope.$broadcast("fileProgress", { total: event.total, loaded: event.loaded }); }; }; var getReader = function(deferred, scope, file) { var reader = new FileReader(); reader.onload = onLoad(reader, deferred, scope,file); reader.onerror = onError(reader, deferred, scope); reader.onprogress = onProgress(reader, scope); return reader; }; var readAsDataURL = function(file, scope) { var deferred = $q.defer(); var reader = getReader(deferred, scope,file); reader.readAsDataURL(file); return deferred.promise; }; return { readAsDataUrl: readAsDataURL }; }]);這里說明一下，部分代碼是參考別人的代碼（http://blog.csdn.net/zx007fack/article/details/41073601），但是對其中內容做了修改，因為用原來的代碼，如果不加前端壓縮功能是正常的，前端壓縮的話因為要用到canvas, 直接用reader.result在ios上圖片的寬高拿到的直接是0，android上是可以的，具體原因不是很確定是不是base64的問題，所以我又直接把file傳了進來，然后用原生js的方法新建圖片元素拿到寬高，再用Canvas進行壓縮，最后轉成blob，通過formData傳給后臺。
3.controller代碼
//選擇圖片后執行的方法 $scope.fileArr = []; $scope.imgSrcArr = [];var i = 0; //為ios上圖片都為image時添加序號 $rootScope.onFileSelect = function(files, event) { //預覽上傳圖片開始 $rootScope.startLoading(); var $this = angular.element(event.target); angular.forEach(files, function(value, index) { var fileIn = value; var fileInName = fileIn.name; var fileType = fileInName.substring(fileInName.lastIndexOf(".") + 1, fileInName.length); //解決ios下所有圖片都為image.jpg的bug if(fileIn) { fileInName = fileInName.split('.')[0] + i + '.' + fileType; i++; } attachvo.push({ name: fileInName, type: fileType }); fileReader.readAsDataUrl(fileIn, $scope) .then(function(result) { result.name = fileInName; $scope.fileArr.push(result); $scope.imgSrcArr.push(URL.createObjectURL(result)); //每次上傳后清空file框，確保每次都能調用change事件 document.querySelector('.upload').reset(); }); $scope.$on('fileProgress', function(event, data) { if(data.total == data.loaded) { $timeout(function() { //上傳圖片結束 $rootScope.endLoading(); }, 200) } }); }); $rootScope.showAttachment = false; };return false; }這里處理了下圖片，在名字上加了序號，因為在ios上每次選擇的圖片名字都叫image,查找了很多資料，說是safari的bug,后面版本才會解決，暫時只能以這種方式解決了。循環是上傳多張圖片
3.html代碼
<ul class="upload-view-ul"> <li ng-repeat="src in imgSrcArr" class="pull-left" ng-click="delCurUpload(src)" ng-class="{'row-last': (($index+1) % 5==0)}"> <span>x</span> <em ng-if='nrc'>{{formData.attachvo[$index].attachmentType}}</em> <img ng-src="{{src}}"> </li> <div class="attachment" pop-type-select ng-if="nrc">+</div> <div class="attachment" ng-if="!nrc"> + <form class="upload"> <input type="file" name="file[]" ng-file-select="onFileSelect($files, $event)" multiple> </form> </div> </ul>4.順便把formdata時代碼貼一下，采用H5上傳圖片的方式
this.FormdataPost = function(pathUrl, formId, formData, files) { var fd = new FormData(); fd.append('formId', formId); if(files && angular.isArray(files)) { files.forEach(function(item) { fd.append('file', item, item.name); }); } fd.append('formData', angular.toJson(formData, true)); var httpConfig = { headers: { 'Authorization': 'Bearer ' + this.token, 'Content-Type': undefined }, transformRequest: angular.identity }; return $http.post(rootUrl + pathUrl, fd, httpConfig).then(function(data) { return data; }).catch(function(error) { $rootScope.interfaceName = pathUrl; $rootScope.setNewWortStatus({ status: error.status, errInfo: error.data && error.data.statusInfo || '' }); return error; }); }思路有一點混亂，不知道講清楚了沒有，想起來再添加吧
以上所述是小編給大家介紹的Angular下H5上傳圖片的方法（可多張上傳），希望對大家有所幫助，如果大家有任何疑問請給我留言，小編會及時回復大家的。在此也非常感謝大家對武林網網站的支持！
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