@angular/common/http

HttpContext

Class

Http context stores arbitrary user defined values and ensures type safety without actually knowing the types. It is backed by a Map and guarantees that keys do not clash.

API

  
    class HttpContext {}

set

HttpContext

Store a value in the context. If a value is already present it will be overwritten.

@paramtokenHttpContextToken<T>

The reference to an instance of HttpContextToken.

@paramvalueT

The value to store.

@returnsHttpContext

get

T

Retrieve the value associated with the given token.

@paramtokenHttpContextToken<T>

The reference to an instance of HttpContextToken.

@returnsT

delete

HttpContext

Delete the value associated with the given token.

@paramtokenHttpContextToken<unknown>

The reference to an instance of HttpContextToken.

@returnsHttpContext

has

boolean

Checks for existence of a given token.

@paramtokenHttpContextToken<unknown>

The reference to an instance of HttpContextToken.

@returnsboolean

keys

IterableIterator<HttpContextToken<unknown>>

@returnsIterableIterator<HttpContextToken<unknown>>

Description

Http context stores arbitrary user defined values and ensures type safety without actually knowing the types. It is backed by a Map and guarantees that keys do not clash.

This context is mutable and is shared between cloned requests unless explicitly specified.

Usage Notes

Usage Example

          // inside cache.interceptors.tsexport const IS_CACHE_ENABLED = new HttpContextToken<boolean>(() => false);export class CacheInterceptor implements HttpInterceptor {  intercept(req: HttpRequest<any>, delegate: HttpHandler): Observable<HttpEvent<any>> {    if (req.context.get(IS_CACHE_ENABLED) === true) {      return ...;    }    return delegate.handle(req);  }}// inside a servicethis.httpClient.get('/api/weather', {  context: new HttpContext().set(IS_CACHE_ENABLED, true)}).subscribe(...);