QB64-PE/internal/help/MID$_(statement).txt

The '''MID$''' statement substitutes one or more new characters for existing characters of a previously defined [[STRING]].



{{PageSyntax}}
:: MID$(''basestring$'', ''start_position%''[, ''bytes%'']) = string_to_add$



* The ''basestring'' variable [[STRING]] value must exist and be large enough to contain the ''string_to_add''.
* ''Start position'' specifies the string character position to start the overwrite. Cannot be 0 or an [[ERROR Codes|Illegal function call error]] will occur!
* The ''byte length'' or number of characters is optional. Excess statement string characters or byte lenghts are ignored.
* The string value to be placed in the string should be as long as the byte length reserved.
* The length of the original string is NOT changed in any case! Excess characters will not be in the string value returned.


''Example:'' Using [[INSTR]] to locate the string positions and a [[MID$ (statement)|MID$]] statement to change the words.

{{CodeStart}}
 text$ = "The cats and dogs were playing, even though dogs don't like cats."
 PRINT text$ 
 start% = 1          ' start cannot be 0 when used in the INSTR function!
 {{Cl|DO...LOOP|DO}}
   position% = {{Cl|INSTR}}(start%, text$, "dog")
   IF position% THEN            ' when position is a value greater than 0
     {{Cl|MID$}}(text$, position%, 3) = "rat"   ' changes "dog" to "rat" when found
     start% = position% + 1     ' advance one position to search rest of string
   END IF
 LOOP UNTIL position% = 0       ' no other matches found
 PRINT text$ '' ''
{{CodeEnd}}
{{OutputStart}}
The cats and dogs were playing, even though dogs don't like cats.
The cats and rats were playing, even though rats don't like cats.
{{OutputEnd}}


''See also:'' 
* [[MID$]] {{text|(function)}}
* [[LEFT$]], [[RIGHT$]] 
* [[INSTR]], [[ASCII]],  [[STR$]], [[HEX$]], [[Bitmaps]] (example)
* [[MKI$]], [[MKL$]], [[MKS$]], [[MKD$]]


{{PageNavigation}}