System.Xml.NonBlockingStreamReader.Read C# (CSharp) Method

		public override int Read ([In, Out] char[] dest_buffer, int index, int count)
		{
			if (base_stream == null)
				throw new ObjectDisposedException ("StreamReader", "Cannot read from a closed StreamReader");
			if (dest_buffer == null)
				throw new ArgumentNullException ("dest_buffer");
			if (index < 0)
				throw new ArgumentOutOfRangeException ("index", "< 0");
			if (count < 0)
				throw new ArgumentOutOfRangeException ("count", "< 0");
			// re-ordered to avoid possible integer overflow
			if (index > dest_buffer.Length - count)
				throw new ArgumentException ("index + count > dest_buffer.Length");

			int chars_read = 0;
//			while (count > 0)
			{
				if (pos >= decoded_count && ReadBuffer () == 0)
					return chars_read > 0 ? chars_read : 0;

				int cch = Math.Min (decoded_count - pos, count);
				Array.Copy (decoded_buffer, pos, dest_buffer, index, cch);
				pos += cch;
				index += cch;
				count -= cch;
				chars_read += cch;
			}
			return chars_read;
		}