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HttpClient.TryGetBufferAsync(Uri) Method

Definition

Send a GET request to the specified Uri and return the response body as HttpGetBufferResult with an IBuffer value in an asynchronous operation. For programming guidance for the HttpClient class, and code examples, see the HttpClient conceptual topic.

public:
 virtual IAsyncOperationWithProgress<HttpGetBufferResult ^, HttpProgress> ^ TryGetBufferAsync(Uri ^ uri) = TryGetBufferAsync;
/// [Windows.Foundation.Metadata.RemoteAsync]
IAsyncOperationWithProgress<HttpGetBufferResult, HttpProgress> TryGetBufferAsync(Uri const& uri);
[Windows.Foundation.Metadata.RemoteAsync]
public IAsyncOperationWithProgress<HttpGetBufferResult,HttpProgress> TryGetBufferAsync(System.Uri uri);
function tryGetBufferAsync(uri)
Public Function TryGetBufferAsync (uri As Uri) As IAsyncOperationWithProgress(Of HttpGetBufferResult, HttpProgress)

Parameters

uri
Uri Uri

The Uri the request is sent to.

Returns

The object representing the asynchronous operation.

Attributes

Windows requirements

Device family
Windows 10, version 1903 (introduced in 10.0.18362.0)
API contract
Windows.Foundation.UniversalApiContract (introduced in v8.0)

Remarks

This method is commonly called when downloading binary content such as small images and compressed files. Very large binary content should be downloaded as a stream with HttpClient.TryGetInputStreamAsync to prevent unneeded buffering.

This operation will not block. The returned IAsyncOperationWithProgress (of HttpGetBufferResult and HttpProgress) completes after the whole response body is read.

The HttpClient class is often used by an app to download and then parse text. It is possible that the character encoding specified in the Content-Type header by an HTTP server does not match the character encoding of the HTTP response body (the XML encoding in an XML document, for example). One way to use HttpClient with text is to call the TryGetStringAsync method and pass the returned string to the text parser. However, this can result in errors if the Content-Type is not a type expressible as a string. A reliable way to use HttpClient with an XML parser is to call the TryGetBufferAsync method and parse the buffer for the "<?xml>" element. Then use the character encoding specified ("<xmlversion="1.0" encoding="UTF-8"?>", for example) to parse the HTTP response body. For other text formats, similar methods can be used where the app scans the initial part of the HTTP response body to determine the character encoding used.

Applies to

See also