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InStr
Gives the position of the first occurrence of one string within another
InStr([start, ]string1, string2[, compare])
The InStr function syntax has these arguments:
| Part |
Description |
| start |
Optional.
Numeric
expression that sets the starting position for each search. If
omitted, search begins at the first character position. If start
contains Null,
an error occurs. The start argument is required if compare
is specified. |
| string1 |
Required.
String
expression being searched. |
| string2 |
Required. String
expression searched for. |
| compare |
Optional. Numeric value
indicating the kind of comparison to use when evaluating substrings.
See Settings section for values. If omitted, a binary comparison is
performed. |
The compare argument can have the following values:
| Constant |
Value |
Description |
|
vbBinaryCompare |
0 |
Perform a
binary comparison. |
|
vbTextCompare |
1 |
Perform a
textual comparison. |
|
vbDatabaseCompare |
2 |
Perform a
comparison based upon information contained in the database where
the comparison is to be performed. |
The Instr function returns the following values:
| If |
InStr returns |
| string1 is
zero-length |
0 |
| string1 is Null |
Null |
| string2 is
zero-length |
start |
| string2 is Null |
Null |
| string2 is not
found |
0 |
| string2 is found
within string1 |
Position at which match
is found |
| start > Len(string2) |
0 |
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| Note Another function (InStrB)
is provided for use with byte data contained in a string. Instead of
returning the character position of the first occurrence of one
string within another, InStrB returns the byte position. |
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