HttpAddRequestHeaders

Important:
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This function adds one or more Hypertext Transfer Protocol (HTTP) request headers to the HTTP request handle.

BOOL WINAPI HttpAddRequestHeaders(
HINTERNET
hHttpRequest
,
LPCTSTR
lpszHeaders
,
DWORD
dwHeadersLength
,
DWORD
dwModifiers
);

Parameters

hHttpRequest

[in] Open HTTP request handle returned by HttpOpenRequest.

lpszHeaders

[in] Long pointer to the null-terminated strings that contains headers to append to the request. Each header must be terminated by a CR/LF (carriage return/line feed) pair.

dwHeadersLength

[in] Specifies the length, in characters, of lpszHeaders. If this parameter is -1L, the function assumes that lpszHeadersis zero-terminated (ASCIIZ), and the length is computed.

dwModifiers

[in] Specifies the values used to modify the semantics of this function. Can be a combination of the following values:

Value	Description
HTTP_ADDREQ_FLAG_ADD	Adds the header if it does not exist. Used with HTTP_ADDREQ_FLAG_REPLACE.
HTTP_ADDREQ_FLAG_ADD_IF_NEW	Adds the header only if it does not already exist; otherwise, an error is returned.
HTTP_ADDREQ_FLAG_COALESCE	Coalesces headers of the same name.
HTTP_ADDREQ_FLAG_COALESCE_WITH_COMMA	Coalesces headers of the same name. For example, adding "Accept: text/" followed by "Accept: audio/" with this flag results in the formation of the single header "Accept: text/, audio/". This causes the first header found to be coalesced. It is up to the calling application to ensure a cohesive scheme with respect to coalesced/separate headers.
HTTP_ADDREQ_FLAG_COALESCE_WITH_SEMICOLON	Coalesces headers of the same name using a semicolon.
HTTP_ADDREQ_FLAG_REPLACE	Replaces or removes a header. If the header value is empty and the header is found, it is removed. If not empty, the header value is replaced.

Return Values

TRUE indicates success. FALSE indicates failure. To get extended error information, call GetLastError.

Remarks

HttpAddRequestHeadersappends additional, free-format headers to the HTTP request handle and is intended for use by sophisticated clients that need detailed control over the exact request sent to the HTTP server.

Note that for basic HttpAddRequestHeaders, the application can pass in multiple headers in a single buffer. If the application is trying to remove or replace a header, only one header can be supplied in lpszHeaders.

Requirements

Runs on	Versions	Defined in	Include	Link to
Windows CE OS	2.0 and later	Wininet.h		Wininet.lib

Note This API is part of the complete Windows CE OS package as provided by Microsoft. The functionality of a particular platform is determined by the original equipment manufacturer (OEM) and some devices may not support this API.