Javascript 如何在角度 2 中正确使用 forEach 循环？
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How to use forEach loop correctly in angular 2?
提问by Vivek
I am new to Angular2 and here I am trying to loop through the array "mmEditorTypes" and checking the condition, if the condition is satisfied then I'll be executing the "open method".
我是 Angular2 的新手，在这里我试图遍历数组“mmEditorTypes”并检查条件，如果条件满足，那么我将执行“open 方法”。
But whenever i execute the below code, I am getting this error :
但是每当我执行以下代码时，我都会收到此错误：
portalModeService: loading of portalMode threw exception:
portalModeService：加载 portalMode 引发异常：
TypeError: Cannot read property 'forEach' of undefined".
类型错误：无法读取未定义的属性“forEach”。
Could someone let me know how to fix this error?
有人可以让我知道如何解决此错误吗？
porta.service.ts :
porta.service.ts ：
function isAppContained(viewState, appType){
let angular:any;
let isContained = false;
angular.forEach(viewState.appViewStates, function (appViewState) {
if (appViewState.signature.appType === appType) {
isContained = true;
}
});
return isContained;
}
回答by Javascript Hupp Technologies
As @Sajeetharan said you can't use angular.forEach in angular 2+
正如@Sajeetharan 所说，你不能在 angular 2+ 中使用 angular.forEach
So you can use simple foreach in typescript like :
因此，您可以在打字稿中使用简单的 foreach，例如：
var someArray = [1, 2, 3];
someArray.forEach((item, index) => {
console.log(item); // 1, 2, 3
console.log(index); // 0, 1, 2
});
回答by Sajeetharan
You cannot use angular.forEachwith angular, its with angularjs.
您不能使用angular.forEachwith angular，它与 angularjs 一起使用。
use
用
for (let appViewState of viewState.appViewStates) {
if (appViewState.signature.appType === appType) {
isContained = true;
}
}
