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Concatenation is a process where literal or variable STRING values are combined using the + operator.


value$ = "Literal text" + string_variable$ + "more text."


  • The STRING values added can be literal or variable string values or a string FUNCTION value.
  • When combining string values in a variable definition, concatenation MUST be used.
  • Literal or variable numerical values cannot be used in string concatenation.
  • A numerical value can be changed to a string value using the STR$(number), CHR$(code), HEX$, OCT$, MKI$, MKS$, MKD$, MKL$, _MK$ or VARPTR$ functions.
  • PRINT does not require any concatenation, but it can be used instead of using semicolons where strings are combined ONLY.
  • String values CANNOT be subtracted from a value. Use LEFT$, RIGHT$ or MID$ to get portions of a string value.


Example 1: Adding quotation marks to a string value using concatenation. Variables cannot be defined using semicolons.

quote$ = CHR$(34) + "Hello World!" + CHR$(34) PRINT "Bill Gates never said "; quote$; " when he answered the telephone!"

Bill Gates never said "Hello World!" when he answered the telephone!

Example 2: Inserting numerical values in a PRINT string with semicolons, PRINT USING and PRINT with concatenation.

name$ = "Billy" boxes% = 102 sales! = 306.00 template$ = "& sold ### boxes for $$####,.##." PRINT name$; " sold"; boxes%; "boxes for $"; sales!; "." PRINT USING template$; name$; boxes%; sales! PRINT name$ + " sold" + STR$(boxes%) + " boxes for $" + LTRIM$(STR$(sales!)) + "."

Billy sold 102 boxes for $ 306 . Billy sold 102 boxes for $306.00. Billy sold 102 boxes for $306.

Explanation: Printed numerical values using semicolons have a space on each side. PRINT USING properly formats the string and displays the cent values when they are zero. STR$ converts the number to a string and excludes the right number space, but leaves the sign space. LTRIM$ eliminates the leading sign space between the string number and the $ dollar sign.

See also

Keyword Reference - Alphabetical
Keyword Reference - By Usage
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