Instr Function

Searches for an exact match of a substring within a String expression and returns the starting position if found (1-n).

...Instr( start, string_t, string_s )

Prerequisites

None

Parameters

start

A required numeric expression. This value specifies the first character position that is tested in string_t. Unlike the IndexOf method, a 1 specifies the first character position in string_t.

string_t

A required String expression. The String expression can be a String variable, constant, function or method, or a concatenation of these String elements. This specifies the target String that is searched for the substring, string_s.

string_s

A required String expression. The String expression can be a String variable, constant, function or method, or a concatenation of these String elements. This specifies the substring value that must be found within the string_t value.

Remarks

This method searches the value of the string_t expression for an exact, case sensitive match to the specified string_s value. The search begins at the character specified by start and continues with successive characters until either the first match is found or the end of the string_t is encountered.

Depending upon the outcome of the search, the values in Table 19-102 are returned by this method.

Table 19-102: Instr Function
String Values	Returned Value
string_s is found in string_t	Character position where the match begins. 1 indicates matched started at the first character of string.
string_t has a zero length	0
string_s has a zero length	start value
string_s not found in string_t	0

Examples

Dim stg_a As String                  ' Create string variable
Dim pos As Integer
stg_a = "aBcDeFgHiJkLmNoPqRsTuVwXyZaBcDeFgHiJk"
pos = Instr(1, stg_a, "Fg")          ' pos will be set to 6
pos = Instr(1, stg_a, "FG")          ' pos will be set to 0
pos = Instr(10, stg_a, "Fg")         ' pos will be set to 32