Pos Function

The Pos function in Delphi returns an integer specifying the position of the first occurrence of one string within another.

It's instantiated like this:

Pos(String,Source);

Pos looks for the first complete occurrence of the specified String — generally offered literally, in single quotes — in Source. The Source is usually some variable. If Pos finds the string, it returns the character position in Source of the first character in Str as an integer value, otherwise it returns 0.

The String and the Source must both be strings.

var s : string;
 i : integer;
 
s:='DELPHI PROGRAMMING';
i:=Pos('HI PR',s);

In this example, the variable i will return the integer 5, because the specified string begins with the letter H, which is in the fifth position in Source.