Difference between revisions of "MID$ (statement)"

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






{{PageSyntax}}
{{PageSyntax}}
:: MID$(''basestring$'', ''start_position%''[, ''bytes%'']) = string_to_add$
: [[MID$]]({{Parameter|baseString$}}, {{Parameter|startPosition%}}[, {{Parameter|bytes%}}]) = {{Parameter|replacementString$}}




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




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


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''See also:''
{{PageSeeAlso}}
* [[MID$]] {{text|(function)}}
* [[MID$]] {{text|(function)}}
* [[LEFT$]], [[RIGHT$]]  
* [[LEFT$]], [[RIGHT$]]  

Revision as of 12:50, 12 October 2017

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


Syntax

MID$(baseString$, startPosition%[, bytes%]) = replacementString$


Description

  • The baseString$ variable must exist and be large enough to contain the replacementString$.
  • startPosition% specifies the string character position to start the overwrite.
  • bytes% or number of characters is optional. Excess byte lenghts are ignored.
  • The replacementString$ should be as long as the byte length reserved.
  • The length of the original string is not changed in any case. If replacementString$ is longer, it gets clipped.


Examples

Example: Using INSTR to locate the string positions and a MID$ statement to change the words.

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! DO position% = INSTR(start%, text$, "dog") IF position% THEN ' when position is a value greater than 0 MID$(text$, position%, 3) = "rat" ' changes "dog" to "rat" when found start% = position% + 1 ' advance one position to search rest of string END IF LOOP UNTIL position% = 0 ' no other matches found PRINT text$

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.


See also



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