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This article will take you through the differences between @, =, & in angular instructions. It has certain reference value. Friends in need can refer to it. I hope it will be helpful to everyone.
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When the scope in the directive is set to an object , this directive has an independent scope, and AngularJS provides a binding strategy for communicating between the isolated scope and the external scope.
1. @(or @attr)
Use the @ symbol for single-item data binding. The value is always a string, so use {{}}.
In addition, this is also a one-way binding. Changes in external data will be reflected internally, but if the internal data changes, the external data will not change.
Attributes should be connected with -, and its camel case format should be written in the scope.
If the attribute name is not specified through @attr, the local name must be consistent with the name of the DOM attribute.
<!DOCTYPE html> <html ng-app="myApp"> <head> <meta charset="utf-8"> <title>AngularJS</title> </head> <body> <div ng-controller="parent"> <div> <input type="text" ng-model="name"/> </div> <my-name show-name="{{name}}"> </my-name> </div> </body> <script type="text/javascript" src="angular.min.js"></script> <script type="text/javascript"> var app = angular.module("myApp", []); app.controller("parent", function($scope){ $scope.name = "Jhon"; }).directive("myName", function(){ return { restrict:"EA", scope:{ showName: '@' // name: '@showName' }, template:'<input type="text" ng-model="showName"/>', // template:'<input type="text" ng-model="name"/>', } }); </script> </html>
2, = (or =attr)
Use = for two-way data binding. Value changes on either side will be reflected on the other side. Because it is a two-way binding, do not use {{}}, otherwise the following demo will report an error.
Attributes should be connected with -, and its camel case format should be written in the scope.
If the attribute name is not specified through @attr, the local name must be consistent with the name of the DOM attribute.
<!DOCTYPE html> <html ng-app="myApp"> <head> <meta charset="utf-8"> <title>AngularJS</title> </head> <body> <div ng-controller="parent"> <div> <input type="text" ng-model="name"/> </div> <my-name show-name="name"> </my-name> </div> </body> <script type="text/javascript" src="angular.min.js"></script> <script type="text/javascript"> var app = angular.module("myApp", []); app.controller("parent", function($scope){ $scope.name = "Jhon"; }).directive("myName", function(){ return { restrict:"EA", scope:{ showName: '=' }, template:'<input type="text" ng-model="showName"/>' } }); </script> </html>
3. &(or &attr)
& is used to bind external functions.
Attributes should be connected with -, and its camel case format should be written in the scope.
If the attribute name is not specified through @attr, the local name must be consistent with the name of the DOM attribute.
76c82f278ac045591c9159d381de2c57 4704c240457a27d06147e4b0954b83f6 93f0f5c25f18dab9d176bd4f6de5d30e 4d0d87937f6c83b675e896c64d3eb7c9 b2386ffb911b14667cb8f0f91ea547a7AngularJS6e916e0f7d1e588d4f442bf645aedb2f 9c3bca370b5104690d9ef395f2c5f8d1 6c04bd5ca3fcae76e30b72ad730ca86d 3cf3733f936ee7ff9ab6793a2dc37e9c dc6dce4a544fdca2df29d5ac0ea9906b 58a4888bfd6bdd4deef6ed9257169b2c 16b28748ea4df4d9c2150843fecfba68 9b92361dfcb7f4f2d4da3631b19fe5e4 43dc565517fdd6198f30dfe101a69eb8 16b28748ea4df4d9c2150843fecfba68 36cc49f0c466276486e50c850b7e4956 144fcfe8d86d863df55fad0ee5374c042cacc6d41bbb37262a98f745aa00fbf0 8019067d09615e43c7904885b5246f0a var app = angular.module("myApp", []); app.controller("parent", function($scope){ $scope.count = 0; $scope.increment = function(){ $scope.count++; }; }).directive("myName", function(){ return { restrict:"EA", scope:{ showName: '&' }, template:'d05c16aa6e8be371f39f1d631fa39062' } }); 2cacc6d41bbb37262a98f745aa00fbf0 73a6ac4ed44ffec12cee46588e518a5e
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