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51 lines
1.9 KiB
Markdown
51 lines
1.9 KiB
Markdown
The [_MEMGET](_MEMGET) statement reads a portion of a memory block at an OFFSET position into a variable, array or user defined type.
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## Syntax
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> [_MEMGET](_MEMGET) memoryBlock, bytePosition, destinationVariable
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* memoryBlock is a [_MEM](_MEM) variable type memory block name created by [_MEMNEW](_MEMNEW) or the [_MEM (function)](_MEM-(function)) function.
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* bytePosition is the memoryBlock.[OFFSET](OFFSET) memory start position plus any bytes to move into the block.
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* destinationVariable is the variable assigned to hold the data. The number of bytes read is determined by the variable [Variable Types](Variable-Types) used.
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## Description
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* The [_MEMGET](_MEMGET) statement is similar to the [GET](GET) statement used in files, but the position is required.
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* The memory block name.[OFFSET](OFFSET) returns the starting byte position of the block. Add bytes to move into the block.
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* The variable type held in the memory block can determine the next bytePosition to read.
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* [LEN](LEN) can be used to determine the byte size of numerical or user defined variable [Variable Types](Variable-Types)s regardless of the value held.
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* [STRING](STRING) values should be of a defined length. Variable length strings can actually move around in memory and not be found.
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## Example(s)
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Shows how to read the PSET color values from a program's [SCREEN](SCREEN) memory to an array.
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```vb
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SCREEN 13
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PSET (0, 0), 123
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PSET (1, 0), 222 'create screen image
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'here is an array
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DIM screen_array(319, 199) AS _UNSIGNED _BYTE 'use screen dimensions from 0
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'here's how we can copy the screen to our array
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DIM m AS _MEM
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m = _MEMIMAGE '0 or no handle necessary when accessing the current program screen
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_MEMGET m, m.OFFSET, screen_array()
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'here's the proof
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PRINT screen_array(0, 0) 'print 123
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PRINT screen_array(1, 0) 'print 222
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END
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```
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## See Also
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* [_MEMGET (function)](_MEMGET-(function))
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* [_MEMPUT](_MEMPUT)
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* [_MEM](_MEM)
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* [_MEMIMAGE](_MEMIMAGE)
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* [_MEMFREE](_MEMFREE)
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