跟我学AngularJS：全局变量设置之value vs constant vs rootscope vs 服务[转]

时间 2019-11-19

标签 angularjs 全局变量设置 value constant rootscope 服务栏目 AngularJS 繁體版

原文原文链接

林炳文Evankaka原创做品。转载请注明出处http://blog.csdn.net/evankakajavascript

摘要：本文要讲讲Angular中value vs. constant以及全局变量的设置html

本教程使用AngularJS版本：1.5.3java

AngularJs GitHub: https://github.com/angular/angular.js/
git

AngularJs下载地址：https://angularjs.org/angularjs

AngualrJS中设置全局变量，即每一个Controller中均可以访问的变量，主要有如下几种方法：github

一、经过var 直接定义global variable，至关于直接用jsapp

2.、用angularjs rootscope来设置全局变量。学习

三、用angularjs value来设置全局变量。测试

四、用angularjs constant来设置全局变量。spa

五、定义服务传值

这里第1种很简单，不说。下面从第2-5来讲说

1、angularjs rootscope来设置全局变量

像使用rootscope，笔者的建议是放在run中，这里其这controller中都不用引入rootscope，直接使用须要的全局变量就能够了。

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appCommon.run(function($rootScope) {
$rootScope.paginationConf = {
currentPage : 1, // 分页开始
itemsPerPage : 15, // 分页每页显示条数
};
})

而后，其它Controller要用，直接

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app.controller('merchantController', function($scope) {
var limit = $scope.paginationConf.itemsPerPage;
var pageIndex = $scope.paginationConf.currentPage;

[html] view plain copy

.......................................
}）

这里须要注意的是，每一个Controller层都会先在当前的scope找须要的变量，找不到，再到rootscope上去寻找。若是仍是找不到，就会报错。

2、用angularjs value来设置全局变量

使用实例以下：

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<!DOCTYPE html>
<html lang="zh" ng-app="myApp">
<head>
<meta charset="UTF-8">
<title>AngularJS学习</title>
<script type="text/javascript" src="./1.5.3/angular.min.js"></script>
</head>
<body>
<div ng-controller="myCtrl1">
<button ng-click="onclick1()">请点击我1</button>
{{value1}}
</div>
<div ng-controller="myCtrl2">
<button ng-click="onclick2()">请点击我2</button>
{{value2}}
</div>
</body>
<script type="text/javascript">
var app = angular.module('myApp', []);
app.value('myValue',{"value1":"林炳文","value2":"hello world",value3:1});
app.controller('myCtrl1', function($scope,myValue) {
$scope.onclick1 = function() {
$scope.value1 = myValue.value1 + (++myValue.value3);
};
});
app.controller('myCtrl2', function($scope,myValue) {
$scope.onclick2 = function() {
$scope.value2 = myValue.value2 + (++myValue.value3);
};
});
</script>
</html>

效果：

3、用angularjs constant来设置全局变量

使用实例

[html] view plain copy

<!DOCTYPE html>
<html lang="zh" ng-app="myApp">
<head>
<meta charset="UTF-8">
<title>AngularJS学习</title>
<script type="text/javascript" src="./1.5.3/angular.min.js"></script>
</head>
<body>
<div ng-controller="myCtrl1">
<button ng-click="onclick1()">请点击我1</button>
{{value1}}
</div>
<div ng-controller="myCtrl2">
<button ng-click="onclick2()">请点击我2</button>
{{value2}}
</div>
</body>
<script type="text/javascript">
var app = angular.module('myApp', []);
app.constant('myConstant',{"value1":"林炳文","value2":"hello world",value3:1});
app.controller('myCtrl1', function($scope,myConstant) {
$scope.onclick1 = function() {
$scope.value1 = myConstant.value1 + (++myConstant.value3);
myConstant.value1 = $scope.value1;
myConstant.value2 = $scope.value1;
};
});
app.controller('myCtrl2', function($scope,myConstant) {
$scope.onclick2 = function() {
$scope.value2 = myConstant.value2 + (++myConstant.value3);
myConstant.value1 = $scope.value2;
myConstant.value2 = $scope.value2;
};
});
</script>
</html>

效果：

value与constant区别

value不可在config里注入，constant能够。下面是笔者作的一个测试

[html] view plain copy

app.constant('myConstant',{"value1":"林炳文","value2":"hello world",value3:1});
app.value('myValue',{"value1":"林炳文","value2":"hello world",value3:1});

而后在config来引入：

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app.config(function(myValue){
..
});

报错以下：

若是使用

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app.config(function(myConstant){
//能够获得constant定义的'myConstant'
});

一切正常

4、定义服务传值

这是Java中最经常使用的方法了，其实就至关于定义一个对象的服务中，并设置get/set方法。经过这两个方法来实时更新与获取数据

[html] view plain copy

<!DOCTYPE html>
<html lang="zh" ng-app="myApp">
<head>
<meta charset="UTF-8">
<title>AngularJS入门学习</title>
<script type="text/javascript" src="./1.5.3/angular.min.js"></script>
</head>
<body>
<div ng-controller="childCtrl1">
{{name}}
<button ng-click="setName()">set name to jack jack jack</button>
</div>
<div ng-controller="childCtrl2">
{{name}}
<button ng-click="setName()">set name to tom tom tom</button>
</div>
</body>
<script type="text/javascript">
var app = angular.module('myApp', []);
app.factory('dataService', function() {
var name = '我是林炳文';
var service = {};
service.getName = function() {
return name;
};
service.setName = function(newName) {
name = newName;
};
return service;
});
app.controller('childCtrl1', function($scope,dataService) {
$scope.name = dataService.getName();
$scope.setName = function() {
dataService.setName( "set name to jack jack jack");
$scope.name = dataService.getName();
};
});
app.controller('childCtrl2', function($scope,dataService) {
$scope.name = dataService.getName();
$scope.setName = function() {
dataService.setName( "set name to tom tom tom");
$scope.name = dataService.getName();
};
});
</script>
</html>

效果：