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ReadChars  
Method  
Reads the next block of characters from the current stream
BinaryReader Class
System.IO NameSpace
CF1.  Function ReadChars ( Count : Integer ) : Array of Char;
CF : Methods with this mark are Compact Framework Compatible
Description
If the current stream has not been exhausted, up to Count characters are returned.
 
The stream position is updated accordingly.
Notes
You must set the length of the target Char array, and it must have sufficient capacity to hold the returned characters.

Compare with the more flexible Read method, where a block of stream characters can be read into an array at a specific array position.
Microsoft MSDN Links
System.IO
System.IO.BinaryReader
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Reading blocks of bytes
program Project1;
{$APPTYPE CONSOLE}

uses
  System.IO;

var
  MyFileStream  : System.IO.FileStream;
  MyFileWriter  : System.IO.BinaryWriter;
  MyFileReader  : System.IO.BinaryReader;
  MyCharArray   : Array of Char;
  Index         : Integer;

begin
  // Create and open our binary file as a stream
  MyFileStream := System.IO.File.Open('C:DelphiBasics.txt',
                                      System.IO.FileMode.Create);

  // Create a BinaryWriter to allow writing to this file
  MyFileWriter := System.IO.BinaryWriter.Create(MyFileStream);

  // Write to the file
  MyFileWriter.Write('A');
  MyFileWriter.Write('B');
  MyFileWriter.Write('C');
  MyFileWriter.Write(49);  // Chr(49) = '1'
  MyFileWriter.Write(50);  // Chr(50) = '2'
  MyFileWriter.Write(51);  // Chr(51) = '3'
  MyFileWriter.Write(52);  // Chr(52) = '4'

  // Close the writer and the stream
  MyFileWriter.Close;
  MyFileStream.Close;

  // Reopen the stream for reading
  MyFileStream := System.IO.File.Open('C:DelphiBasics.txt',
                                      System.IO.FileMode.Open);

  // Create a BinaryReader to allow the file to be read back
  MyFileReader := System.IO.BinaryReader.Create(MyFileStream);

  // Declare our array to hold the returned data
  SetLength(MyCharArray, 10);

  // Get the whole file contents into our array
  // Note that we do not necessarily get the same number of
  //      characters that we request : we actually get 7 here
  MyCharArray := MyFileReader.ReadChars(10);

  // Display our array contents
  Console.WriteLine(MyCharArray);

  // Close the reader and the stream
  MyFileReader.Close;
  MyFileStream.Close;

  Console.Readline;
end.
   ABC1234
 
 
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