Class PagedAsyncEnumerable<TResponse, TResource> (4.0.0)

public abstract class PagedAsyncEnumerable<TResponse, TResource> : IAsyncEnumerable<TResource>

An asynchronous sequence of resources obtained via API responses. Application code can treat this as a simple sequence (with API calls automatically being made lazily as more results are required), or call AsRawResponses() to retrieve one API response at a time, potentially with additional information.

Inheritance

Object > PagedAsyncEnumerable<TResponse, TResource>

Derived Types

GrpcPagedAsyncEnumerable<TRequest, TResponse, TResource>

RestPagedAsyncEnumerable<TRequest, TResponse, TResource>

Namespace

Google.Api.Gax

Assembly

Google.Api.Gax.dll

Type Parameters
Name	Description
`TResponse`	The API response type. Each response contains a page of resources.
`TResource`	The resource type contained within the response.

Methods

AsRawResponses()

public virtual IAsyncEnumerable<TResponse> AsRawResponses()

Returns the sequence of raw API responses, each of which contributes a page of resources to this sequence.

Returns
Type	Description
`IAsyncEnumerable<TResponse>`	An asynchronous sequence of raw API responses, each containing a page of resources.

GetAsyncEnumerator(CancellationToken)

public virtual IAsyncEnumerator<TResource> GetAsyncEnumerator(CancellationToken cancellationToken = default(CancellationToken))

Parameter
Name	Description
`cancellationToken`	`CancellationToken`

Returns
Type	Description
`IAsyncEnumerator<TResource>`

ReadPageAsync(Int32, CancellationToken)

public virtual Task<Page<TResource>> ReadPageAsync(int pageSize, CancellationToken cancellationToken = default(CancellationToken))

Eagerly (but asynchronously) reads a single page of results with a fixed maximum size. The returned page is guaranteed to have that many results, unless there is no more data available.

Parameters
Name	Description
`pageSize`	`Int32` The page size. Must be greater than 0.
`cancellationToken`	`CancellationToken` A token to cancel the operation.

Returns
Type	Description
`Task<Page<TResource>>`	An asynchronous operation, the result of which is a page of resources.

Remarks

"Natural" pages returned by the API may contain a smaller number of resources than requested. For example, a request for a page with 100 resources may return a page with 80 resources but a next page token for more to be retrieved. This is suitable for batch-processing, but not for user-visible paging such as in a web application, where fixed-size pages are expected. This method may make more than one API call in order to fill the page, but after the page has been returned, all the data will have been loaded. (In particular, iterating over the items in the page multiple times will not make any further requests.)