The LEFT$ string function returns a number of characters from the left of a STRING.
Syntax
LEFT$(stringValue$, numberOfCharacters%)
Parameter(s)
- stringValue$ can be any STRING literal or variable.
- numberOfCharacters% INTEGER determines the number of characters to return from left of string.
Description
- If the number of characters exceeds the string length the entire string is returned. Use LEN to determine a string’s length.
- LEFT$ returns always start at the first character of the string, even if it’s a space. LTRIM$ can remove leading spaces.
- numberOfCharacters% cannot be a negative value.
Example(s)
Getting the left portion of a string value.
name$ = "Tom Williams"
First$ = LEFT$(name$, 3)
PRINT First$
Tom
A replace function using LEFT$ and RIGHT$ with INSTR to insert a different length word into an existing string.
text$ = "This is my sentence to change my words."
PRINT text$
oldword$ = "my"
newword$ = "your"
x = Replace(text$, oldword$, newword$)
IF x THEN PRINT text$; x
END
FUNCTION Replace (text$, old$, new$) 'can also be used as a SUB without the count assignment
DO
find = INSTR(start + 1, text$, old$) 'find location of a word in text
IF find THEN
count = count + 1
first$ = LEFT$(text$, find - 1) 'text before word including spaces
last$ = RIGHT$(text$, LEN(text$) - (find + LEN(old$) - 1)) 'text after word
text$ = first$ + new$ + last$
END IF
start = find
LOOP WHILE find
Replace = count 'function returns the number of replaced words. Comment out in SUB
END FUNCTION
This is my sentence to change my words.
This is your sentence to change your words.
Note: The MID$ (statement) statement can only substitute words or sections of the original string length. It cannot change the string length.