/// <summary>
/// Converts a String in the form 0011AABB to a Byte[] using the chars in the string as bytes to caulcate the decimal value.
/// </summary>
/// <notes>
/// Reduced string allocations from managed version substring
/// About 10 milliseconds faster then Managed when doing it 100,000 times. otherwise no change
/// </notes>
/// <param name="str"></param>
/// <returns></returns>
public static byte[] HexStringToBytes(string str, int start = 0, int length = -1, bool onlyLettersOrDigits = true)
{
//Dont check the results for overflow
unchecked
{
if (length.Equals(Common.Binary.Zero))
{
return(null);
}
if (length <= -1)
{
length = str.Length;
}
int check = length - start;
if (start > check)
{
throw new System.ArgumentOutOfRangeException("start");
}
if (length > check)
{
throw new System.ArgumentOutOfRangeException("length");
}
System.Collections.Generic.IEnumerable <byte> result = Media.Common.MemorySegment.EmptyBytes;
//Iterate the pointer using the managed length ....
//Todo, optomize with reverse or i - 1
for (int i = start, e = length; i < e; i += 2)
{
//to reduce string manipulations pre call
if (onlyLettersOrDigits && char.IsLetterOrDigit(str[i]).Equals(false))
{
//Back up 1
--i;
//Increase by 2
continue;
}
//Todo, Native and Unsafe
//Convert 2 Chars to a byte
result = System.Linq.Enumerable.Concat(result, LinqExtensions.Yield((byte)(HexCharToByte(str[i]) << 4 | HexCharToByte(str[i + 1]))));
}
//Dont use a List..
//Return the bytes
return(System.Linq.Enumerable.ToArray(result));
}
}
/// <summary>
/// Creates a delegate from a MethodInfo using <see cref="System.Linq.Expressions.Expression.GetDelegateType"/>
/// </summary>
/// <param name="method"></param>
/// <returns></returns>
public static System.Delegate CreateDelegate(System.Reflection.MethodInfo method)
{
if (method == null)
{
throw new System.ArgumentNullException("method");
}
return(method.CreateDelegate(System.Linq.Expressions.Expression.GetDelegateType(method.GetParameters().Select(p => p.ParameterType).Concat(LinqExtensions.Yield(method.ReturnType)).ToArray())));
}
