.NET Documentation

HttpParserStateFlags Enum

In: System.Net.Http.Headers

Summary

Flags that indicate the current parsing state for HTTP headers. These flags are used internally by the HTTP parsing engine to manage context and track progress during header parsing.

Members

None (0)
ParsingHeaderName (1)
ParsingHeaderValue (2)
SkippingWhiteSpace (4)
InQuotes (8)
InToken (16)
StartOfLine (32)

Remarks

The HttpParserStateFlags enum provides a set of bit flags that represent various states encountered during the parsing of HTTP headers. These flags are primarily used by internal components of the .NET networking stack. Developers typically do not need to interact with this enum directly. It helps in managing the parsing process by indicating whether the parser is currently reading a header name, a header value, skipping whitespace, or if it's within quoted strings or tokens. The combination of these flags allows for robust and accurate interpretation of HTTP header fields, even with complex or malformed inputs.

Usage Example (Internal)

The following code snippet illustrates how these flags might be used internally during header parsing. This is for conceptual understanding and not meant for direct use. 


// Internal parsing logic sketch
HttpParserStateFlags currentState = HttpParserStateFlags.StartOfLine | HttpParserStateFlags.SkippingWhiteSpace;
char currentChar = ' ';

if ((currentState & HttpParserStateFlags.SkippingWhiteSpace) != 0) {
    // Consume whitespace
    currentState &= ~HttpParserStateFlags.SkippingWhiteSpace; // Remove flag once done
    currentState |= HttpParserStateFlags.ParsingHeaderName;
}

if ((currentState & HttpParserStateFlags.ParsingHeaderName) != 0) {
    if (currentChar == ':') {
        currentState &= ~HttpParserStateFlags.ParsingHeaderName;
        currentState |= HttpParserStateFlags.ParsingHeaderValue;
    } else {
        // Append char to header name buffer
    }
}

// ... more complex logic involving other flags ...

See Also