InStr (Find In String)

The InStr function is used to find the location of a string within a string.

Syntax

Variable = InStr ( Start, SearchString, FilterString, SearchOption )

In the following program example, the Instr instruction is used to find the position of the text "direction:" in a string (SearchString). The result is stored in the variable Start1.

Public SearchString AS STRING * 80
Public FilterString1 AS STRING * 20
Public Start1

BeginProg
  SearchString = "maximum wind speed: 100 mph; direction: 263 degrees; Site 11 Cedar Mountain."
  FilterString1 = "direction:"
  Scan (1,Sec,0,0)
    Start1 = InStr (1,SearchString,FilterString1,2)
  NextScan
EndProg

Remarks

This function returns the integer position of the first occurrence of the FilterString parameter. If the FilterString is not found, the function returns 0.

Parameters

Start

Specifies where in the SearchString to begin. A 1 indicates the first character in the string.

Type: Integer

SearchString (Search String)

The string to evaluate.

Type: String or variable

FilterString (Filter String)

The string to look for in the SearchString.

Type: String

For a FilterString using non-printable ASCII characters, use the CHR function and the appropriate ASCII code.

SearchOption (Search Option)

A code used to help define the method of searching.

Code Description
0 NUMERIC - Numerics in the SearchString (FilterString is ignored).
1 NON-NUMERIC - Non-numerics (FilterString is ignored).
2 SEARCHSTRING - Each FilterStrings in SearchString.
3 SEARCHCHARS - Each occurrence of any character that is in FilterString.
4 HEADERFILTER - Strings succeeding FilterString.
6 HEADERFILTERCHARS - Strings succeeding any character in the FilterString char list.
8 NUMERICHEX - Hexadecimal numerics in the SearchString (FilterString is ignored).
9 ReverseCS – first occurrence of the filter string, searching from the end of the string. Case sensitive.
10 ReverseIS - first occurrence of the filter string, searching from the end of the string. Case insensitive.

Add 100 to any of the non-numeric options above to parse a string that includes quotes, with the quotes being omitted in the result.

Type: Constant

String variables can be declared as only one or two dimensions; for example, String(x) or String(x,y). To begin reading or modifying a string at a particular location into the string, enter the location as a third dimension; for example, String(x,y,n) where n is the desired character. For example, given an array of strings Str(10,10), Str(2,2,n) refers to n character in the (2,2) element of the array. Use Str(1,1,n) for a scalar variable and Str(x,1,n) for a one dimensional array element.

WARNING: String functions are case sensitive. Uppercase or lowercase can be used to convert to all one case prior to processing the string if desired.