| Description |
The GetMem procedure attempts to get the specified StorageSize bytes of storage, storing a pointer to the storage in StoragePointer.
If the allocation fails, then a EOutOfMemory exception is raised.
The storage is not initialised in any way.
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| Notes |
The GetMem procedure is Thread safe as long as IsMultiThread is true.
It is better to use New to allocate storage for records - the example is for illustration of GetMem and pointer manipulation.
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| Related commands |
| Dispose |
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Dispose of storage used by a pointer type variable |
| FillChar |
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Fills out a section of storage with a fill character or byte value |
| FreeMem |
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Free memory storage used by a variable |
| New |
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Create a new pointer type variable |
| ReallocMem |
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Reallocate an existing block of storage |
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| Example code : Get storage for 3 records and use this storage |
// Full Unit code.
// -----------------------------------------------------------
// You must store this code in a unit called Unit1 with a form
// called Form1 that has an OnCreate event called FormCreate.
unit Unit1;
interface
uses
// The System unit does not need to be defined
Forms, Dialogs;
type
TForm1 = class(TForm)
procedure FormCreate(Sender: TObject);
end;
var
Form1: TForm1;
implementation
{$R *.dfm} // Include form definitions
procedure TForm1.FormCreate(Sender: TObject);
type
TRecord = Record
name : string[10];
age : Byte;
end;
var
recPointer : ^TRecord;
begin
// Allocate storage for three records
// Note : It is better to use New for this
// It is used here for illustration purposes only
GetMem(recPointer, 3 * SizeOf(TRecord));
// Fill out these 3 records with values
recPointer.name := 'Brian';
recPointer.age := 23;
Inc(recPointer);
recPointer.name := 'Jim';
recPointer.age := 55;
Inc(recPointer);
recPointer.name := 'Sally';
recPointer.age := 38;
// Now display these values
Dec(recPointer, 2);
ShowMessageFmt('%s is %d',[recPointer.name, recPointer.age]);
Inc(recPointer);
ShowMessageFmt('%s is %d',[recPointer.name, recPointer.age]);
Inc(recPointer);
ShowMessageFmt('%s is %d',[recPointer.name, recPointer.age]);
end;
end.
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| Hide full unit code |
Brian is 23
Jim is 55
Sally is 38
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