Esempio n. 1
0
 /// <summary>
 /// Helper method to try to peek next value from this <see cref="PeekablePotentiallyAsyncReader{TValue}"/>, or throw if no more values can be read.
 /// </summary>
 /// <typeparam name="TValue">The type of values that this reader produces.</typeparam>
 /// <param name="reader">This <see cref="PeekablePotentiallyAsyncReader{TValue}"/>.</param>
 /// <param name="checker">Optional callback to check value. If it is supplied, this method will keep reading values until this callback returns <c>true</c>.</param>
 /// <returns>A task which will return last value peeked.</returns>
 /// <exception cref="NullReferenceException">If this <see cref="PeekablePotentiallyAsyncReader{TValue}"/> is <c>null</c>.</exception>
 /// <exception cref="EndOfStreamException">If no more values could be read from the source.</exception>
 public static async ValueTask <TValue> PeekUntilAsync <TValue>(
     this PeekablePotentiallyAsyncReader <TValue?> reader,
     Func <TValue, Boolean> checker
     )
     where TValue : struct
 {
     return(await reader.TryPeekUntilAsync(checker) ?? throw new EndOfStreamException());
 }
Esempio n. 2
0
    /// <summary>
    /// Helper method to try to peek next value from this <see cref="PeekablePotentiallyAsyncReader{TValue}"/> until suitable value has been read, or values will end.
    /// </summary>
    /// <typeparam name="TValue">The type of values that this reader produces.</typeparam>
    /// <param name="reader">This <see cref="PeekablePotentiallyAsyncReader{TValue}"/>.</param>
    /// <param name="checker">Optional callback to check value. If it is supplied, this method will keep reading values until this callback returns <c>true</c>.</param>
    /// <returns>A task which will return last value peeked.</returns>
    /// <exception cref="NullReferenceException">If this <see cref="PeekablePotentiallyAsyncReader{TValue}"/> is <c>null</c>.</exception>
    public static async ValueTask <TValue?> TryPeekUntilAsync <TValue>(
        this PeekablePotentiallyAsyncReader <TValue?> reader,
        Func <TValue, Boolean> checker
        )
        where TValue : struct
    {
        ArgumentValidator.ValidateNotNullReference(reader);
        var val = await reader.TryPeekAsync();

        while (val.HasValue && !(checker?.Invoke(val.Value) ?? true))
        {
            await reader.TryReadNextAsync();

            val = await reader.TryPeekAsync();
        }

        return(val);
    }