Home > Article > Web Front-end > A brief discussion on the differences of @, =, & instructions in angular
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.
[Related recommendation: "angular tutorial"]
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
For more programming-related knowledge, please visit: Programming Video! !
The above is the detailed content of A brief discussion on the differences of @, =, & instructions in angular. For more information, please follow other related articles on the PHP Chinese website!