Delegate ValueParserDelegate

Tries to parse a single route segment into a value that can optionally be stored in Parameters.

Namespace: NanoRoute

Assembly: NanoRoute.dll

Syntax

public delegate ValueTask<ValueParseResult> ValueParserDelegate(ValueParserContext context)

Parameters

Type	Name	Description
ValueParserContext	context	The parser context, including the decoded route segment, request services, and the linked pipeline cancellation token.

Returns

Type	Description
ValueTask<ValueParseResult>	A ValueParseResult that describes whether the segment matched and what value it produced.

Remarks

Exceptions thrown by the delegate propagate during request processing for matching routes that use the parser.

Examples

routerBuilder.AddValueParser("user", static async (ValueParserContext context) =>
{
    if (!Guid.TryParse(context.Segment.ToString(), out Guid userId))
        return ValueParseResult.False;

    object? user = await context
        .Services
        .GetRequiredService<IUserRepository>()
        .TryGetAsync(userId, context.Cancellation);

    return new ValueParseResult(user is not null, user);
});