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--- read_file_stream [2018/01/27 20:14] – created wolfgangriedmann
+++ read_file_stream [2018/01/27 20:44] (current) – wolfgangriedmann
@@ Line 1: / Line 1: @@
 ====== Read a file using a stream ======
+If you need to read a larger file and process it during the read, you should use a ''stream'' for it.
+This is largely used when reading or writing in the network using internet protocols.
+This is a sample how to read a file using a stream:
+<code>using System.IO
+using System.Text
+function ReadFileStream( cFileName as string ) as void
+local oFileStream as FileStream
+local aBytes as byte[]
+local nOffset as int
+local nRead as int
+local nBufLen as int
+local cBuffer as string
+nOffset	:= 0
+nBufLen := 10
+cBuffer	:= ""
+aBytes := byte[]{ 10 }
+oFileStream := FileStream{ cFileName, FileMode.Open, FileAccess.Read }
+while ( nRead := oFileStream:Read( aBytes, 0, nBufLen ) ) > 0
+  cBuffer := cBuffer + System.Text.Encoding.UTF32:GetString( aBytes )
+  nOffset := nOffset + nRead
+end
+System.Console.WriteLine( "Read with stream:" + cBuffer )
+return</code>
+You will find more information about the [[https://docs.microsoft.com/en-us/dotnet/api/system.io.stream|System.IO.Stream]] class in the MSDN, together with the child classes like the FileStream class.
+Please pay attention to the correct [[encodings|Encoding]]!