Find the detail of SSC CGL syllabus of each section and marking scheme and weight-age of each topic and focus area of topics to score maximum marks in exam – quantitative aptitude , Reasoning , English and General Awareness. SSC Exam Pattern and Marking Scheme Time Limit – 60 minutes Total number of questions – […]
Custom Validations in Angular Forms
We often are going to want to write our own custom validations. To see how validators are implemented, let’s look at Validators.required from the Angular core source:
|
1 2 3 4 5 6 |
export class Validators { static required(c: FormControl): StringMap<string, boolean> { return isBlank(c.value) || c.value == "" ? {"required": true} : null; } |
A validator: – Takes a FormControl as its input and – Returns a StringMap<string, boolean> where the key is “error code” and the value is true if it fails Writing […]
Dependency Injection in Angular
As our programs grow in size, parts of the app need to communicate with other modules. When module A requires module B to run, we say that B is a dependency of A. One of the most common ways to get access to dependencies is to simply import a file. For instance, in this hypothetical module we might […]
Dependency Injection Parts in Angular
To register a dependency we have to bind it to something that will identify that dependency. This identification is called the dependency token. For instance, if we want to register the URL of an API, we can use the string API_URL as the token. Similarly, if we’re registering a class, we can use the class itself as its […]
Providing Dependencies with NgModule in Angular
While it’s interesting to see how an injector is created directly, that isn’t the typical way we’d use injections. Instead, what we’d normally do is 1) use NgModule to register what we’ll inject – these are called providers 2) use decorators (generally on a constructor) to specify what we’re injecting By doing these two steps Angular […]
- 1
- 2
- 3
- …
- 1381
- Next Page »