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