mid

The mid function extracts from a specified position in a string, either to the end of the string or for a specified number of characters and returns the resultant string. This function is zero-based.

Common use

The mid function is often used with the strstr function. The strstr function will return the position of a specific character, then the mid can be used to return a substring from that character.

Because the mid function is zero-based, it is often used incorrectly, with the resultant string off by one character. An easy way to determine the correct starting position is to envision a cursor and count how many times you need to move it to get to the starting position you want. See the example below.

Syntax

string_variable = mid(string_variable,start_pos,num_char)

where:

string_variable = The variable containing the string you want to extract.
start_pos = The starting position in the string of characters (integer).
num_char = The number of characters from the starting position (integer).

Note: You may not use an ActiveX property as the first parameter of the mid function because the length of the property is unknown prior to compilation.

Example

string [25]name;
string [10]temp_variable;
name = "Acme Shipping Company"
temp_variable = mid(name,5,8);
//The map will read 8 characters in the string starting with
//the sixth character. It is essentially ignoring the first
//five characters, so "temp_variable" will contain "Shipping".