Angularjs实现上传图片预览功能

  app.factory("fileReader", function($q, $log) { var onLoad = function(reader, deferred, scope) { return function () { scope.$apply(function () { deferred.resolve(reader.result); }); }; }; 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) { var reader = new FileReader(); reader.onload = onLoad(reader, deferred, scope); 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); reader.readAsDataURL(file); return deferred.promise; }; return { readAsDataUrl: readAsDataURL }; });

 $scope.onFileSelect = function(files) { var fileIn=files[0]; var img = new Image(); var fileType = fileIn.name.substring(fileIn.name.lastIndexOf(".") + 1, fileIn.name.length); if(fileIn.size>5242880){//单位是B，此处不允许超过5M alert("图片不能超过5M") return; } if(fileType=='JPG' || fileType=='PNG' || fileType=='JPEG ' || fileType=='jpg' || fileType=='png' || fileType=='jpeg'){ }else{ alert("图片格式只支持:JPG,PNG,JPEG") return; } fileReader.readAsDataUrl(fileIn, $scope) .then(function(result) { $scope.imageSrc = result; console.log(img.width); }); }