angular readfile

var app=angular.module("myApp",[]);
//指令1
app.directive("fileread", [function () {
    return {
        scope: {
            fileread: "="
        },
        link: function (scope, element, attributes) {
            element.bind("change", function (changeEvent) {
                var reader = new FileReader();
                reader.onload = function (loadEvent) {
                    scope.$apply(function () {
                        scope.fileread = loadEvent.target.result;
                    });
                }
                reader.readAsDataURL(changeEvent.target.files[0]);
            });
        }
    }
}]);
//指令2
app.directive("fileread", [function () {
    return {
        scope: {
            fileread: "="
        },
        link: function (scope, element, attributes) {
            element.bind("change", function (changeEvent) {
                scope.$apply(function () {
                    scope.fileread = changeEvent.target.files[0];
                    // or all selected files:
                    // scope.fileread = changeEvent.target.files;
                });
            });
        }
    }
}]);
//指令3（异步）
app.directive('appFilereader', function($q) {
    var slice = Array.prototype.slice;
    return {
        restrict: 'A',
        require: '?ngModel',
        link: function(scope, element, attrs, ngModel) {
                if (!ngModel) return;
                ngModel.$render = function() {};
                element.bind('change', function(e) {
                    var element = e.target;
                    $q.all(slice.call(element.files, 0).map(readFile))
                        .then(function(values) {
                            if (element.multiple) ngModel.$setViewValue(values);
                            else ngModel.$setViewValue(values.length ? values[0] : null);
                        });
                    function readFile(file) {
                        var deferred = $q.defer();

                        var reader = new FileReader();
                        reader.onload = function(e) {
                            deferred.resolve(e.target.result);
                        };
                        reader.onerror = function(e) {
                            deferred.reject(e);
                        };
                        reader.readAsDataURL(file);

                        return deferred.promise;
                    }

                }); //change

            } //link
    }; //return
});