TProxyStream.Seek function
Sets the current position in the stream.
Declaration
function Seek(const Offset: Int64; Origin: TSeekOrigin): Int64
; overrideDescription
Seek sets the position of the stream to
Offset bytes
from
Origin. There is a 32-bit variant of this function and a
64-bit variant. The difference can be made by choosing the correct
Offset parameter: the integer-typed parameter selects the 32-bit
variant, the parameter of type
TSeekOrigin selects the 64-bit
variant of the function.
Both variants of this function return the new (0-based) position in the stream.
The Origin parameter for the 32-bit version can have one of the following values:
| Constant | Meaning |
| soFromBeginning | Set the position relative to the start of the stream. |
| soFromCurrent | Set the position relative to the current position in the stream. |
| soFromEnd | Set the position relative to the end of the stream. |
These values are defined in the SysUtils unit.
The Origin parameter for the 64-bit version has one of the following values:
| Value | Meaning |
| soBeginning |
Offset is interpreted relative to the start of the stream. |
| soCurrent |
Offset is interpreted relative to the current position in the stream. |
| soEnd |
Offset is interpreted relative to the end of the stream. |
Offset should be negative when the origin is
SoFromEnd (
soEnd).
It should be positive for
soFromBeginning and can have both signs for
soFromCurrent
This is an abstract method, which must be overridden by descendant classes.
They may choose not to implement this method for all values of
Origin and Offset.
TStream, the 64-bit version of the call should
be overridden.
Errors
An exception may be raised if this method is called with an invalid pair of
Offset,
Origin values. e.g. a negative
offset for
soFromBeginning (or
soBeginning).
This description is the one of Classes.TStream.Seek.
See also
An experiment, built from development snapshots. Not the official Free Pascal or Lazarus documentation.