Pascal has many routines for working with strings. Many of them are called using dot notation and are called **methods**. A complete list of string manipulation methods can be found online.

Let's get acquainted with some of them.

s := 'aAbBcC'
sUp := uppercase(s); // sUp = "AABBCC" - a method that converts each character of a string to uppercase
sLow := `lowercase(s) //`

sLow = "aabbcc" - a method that converts each character of a string to lowercase

The method is always written with parentheses. There are some parameters inside the brackets, if they are needed.

Another useful method - val

`(s, v, ind)`

- method to check if all characters of a string are digits.

**s** - source string,

**v** contains a number if the source string was a number, and 0 otherwise,

**ind** contains the number of the first

** index s** which is not a digit, or 0 if s

** ** is a number.

s := 'ab1c'
val(s, v, ind);
writeln(v, ' ', ind); // 0 3
s := '123';
val(s, v, ind);
w(vriteln, ' ', ind); // 123 0

The useful trim(s) - method allows you to remove spaces at the beginning and end of a string

s := ' ab 1c ';
print('s=', trim(s)); // s=ab 1c