这是我的指令如何转换成组件?我正在将我的应用程序转换为angular 1.5。 如何将此指令转换为组件?这是我想要转换为组件的文件上传指令。
app.directive('ngThumb', ['$window', function($window) {
var helper = {
support: !!($window.FileReader && $window.CanvasRenderingContext2D),
isFile: function(item) {
return angular.isObject(item) && item instanceof $window.File;
},
isImage: function(file) {
var type = '|' + file.type.slice(file.type.lastIndexOf('/') + 1) + '|';
return '|jpg|png|jpeg|bmp|gif|'.indexOf(type) !== -1;
}
};
return {
restrict: 'A',
template: '<canvas/>',
link: function(scope, element, attributes) {
if (!helper.support) return;
var params = scope.$eval(attributes.ngThumb);
if (!helper.isFile(params.file)) return;
if (!helper.isImage(params.file)) return;
var canvas = element.find('canvas');
var reader = new FileReader();
reader.onload = onLoadFile;
reader.readAsDataURL(params.file);
function onLoadFile(event) {
var img = new Image();
img.onload = onLoadImage;
img.src = event.target.result;
}
function onLoadImage() {
var width = params.width || this.width / this.height * params.height;
var height = params.height || this.height / this.width * params.width;
canvas.attr({ width: width, height: height });
canvas[0].getContext('2d').drawImage(this, 0, 0, width, height);
}
}
};
}]);
答案 0 :(得分:4)
需要使用控制器而不是链接功能,并将$element
注入控制器
.component("ngThumb", ['$window', function($window) {
var helper = {
support: !!($window.FileReader && $window.CanvasRenderingContext2D),
isFile: function(item) {
return angular.isObject(item) && item instanceof $window.File;
},
isImage: function(file) {
var type = '|' + file.type.slice(file.type.lastIndexOf('/') + 1) + '|';
return '|jpg|png|jpeg|bmp|gif|'.indexOf(type) !== -1;
}
};
return {
//link fn is deprecated now
controller: function($scope, $element) {
if (!helper.support) return;
var params = $scope.$eval($element[0].ngThumb);
if (!helper.isFile(params.file)) return;
if (!helper.isImage(params.file)) return;
var canvas = $element.find('canvas');
var reader = new FileReader();
reader.onload = onLoadFile;
reader.readAsDataURL(params.file);
function onLoadFile(event) {
var img = new Image();
img.onload = onLoadImage;
img.src = event.target.result;
}
function onLoadImage() {
var width = params.width || this.width / this.height * params.height;
var height = params.height || this.height / this.width * params.width;
canvas.attr({
width: width,
height: height
});
canvas[0].getContext('2d').drawImage(this, 0, 0, width, height);
}
},
template: '<canvas/>'
}
}])