Typed Files

What is translated > File Input and Output > Typed Files

A Delphi declaration of the form file of T is translated to TypedFile<T>.

A typed file stores a sequence of values with a fixed record size.

For example, a Delphi file of Word is translated to:

TypedFile<ushort> myFile =

    TypedFile<ushort>.CreateRecord();

The record size is determined from the element type. For ushort, the record size is two bytes.

A typed file is written as follows:

AssignFile(myFile, "Words.dat");

Rewrite(myFile);

Write(myFile, (ushort)234);

Write(myFile, (ushort)567);

CloseFile(myFile);

The file can later be reopened and read:

ushort value = 0;

Reset(myFile);

while (!Eof(myFile))

{

    Read(myFile, ref value);

}

CloseFile(myFile);

TypedFile<T> requires a fixed-size value type. Types containing managed references, such as strings, dynamic arrays, classes, objects, or interfaces, cannot be stored directly.

When binary compatibility with Delphi is required, the generated C# record layout must match the original Delphi record layout.

This page belongs to the Delphi2C# Documentation