In Delphi, you can use several different techniques to allocate memory for your programs. Here are a few examples:
Allocating memory using the GetMem function: The GetMem function is used to allocate a block of memory of a specified size. You can then use the memory block to store data or to create an object. For example:
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var MyArray: array of Integer; begin SetLength(MyArray, 100); // Allocate memory for 100 integers GetMem(MyArray, SizeOf(Integer) * 100); // Allocate memory manually end; |
Allocating memory for objects using the New function: The New function is used to create an instance of a class and allocate memory for it on the heap. For example:
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type TMyClass = class private FValue: Integer; public constructor Create; destructor Destroy; override; end; constructor TMyClass.Create; begin inherited; FValue := 0; end; destructor TMyClass.Destroy; begin inherited; end; var MyObject: TMyClass; begin MyObject := TMyClass.Create; // Allocate memory for the object MyObject.Free; // Free the memory when you are finished with it end; |
Allocating memory for records using the GetMem function: You can use the GetMem function to allocate memory for a record and then use the PByte type to access the fields of the record. For example:
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type TMyRecord = record Value1: Integer; Value2: Integer; end; var MyRecord: ^TMyRecord; begin GetMem(MyRecord, SizeOf(TMyRecord)); // Allocate memory for the record MyRecord.Value1 := 10; // Access the fields of the record MyRecord.Value2 := 20; FreeMem(MyRecord); // Free the memory when you are finished with it end; |
These are just a few examples of how you can allocate memory in Delphi. It is important to free the memory when you are finished with it to prevent memory leaks. You can use the FreeMem function to free memory allocated with GetMem, and you can use the Free method to free memory allocated for objects.
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