Functions (characters and strings)

Pascal's commonly used character processing standard function has 5

(1) Ord (CH) for the ASCII code value corresponding to the character ch, such as ord (' A ') result is 65,ord (true) result is 1,ord (false) result is 0
(2) Chr (x) for x (x 1 ... 255 integers) of the asii code corresponding to the character, such as: Chr (65) result is ' A '.
(3) pred (CH) precursor function pred (' B ') result is ' A '
(4) SUCC (CH) successor function succ (' B ') result is ' C '

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Pascal commonly used string processing standard function has 4

(1) Copy (str,n,m) from the left nth of the string str to intercept m characters, such as: Copy (' Pascal ', 3,2) The result is ' SC ';

(2) concat (STR1,STR2) connects two strings into a new string, such as: s:=str1+str2; equals two string of characters added

(3) Length (str) of the string str (number of characters);

(4) POS (STR1,STR2) The position of the string str1 the beginning of the string, if not found, the function value is 0. such as: POS (' SCA ', ' Pascal ') result is 3;

(5) upcase (CH) converts all characters of the string str to uppercase letters, such as the UpCase (' abc ') result as ' abc ';

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Pascal commonly used string processing standard process has 4

(1) Val (str,x) converts a numeric string into a number and is stored in the variable x, such as Val (' 68|val ', x), x value is 9|val (' 9 ', x) x value is 0 (' A9 ', x) x value)

(2) str (N,S) converts the number n into a string in s, such as the result of STR (768,s) s is ' 768 ';

(3) Insert (Str1,str2,n) inserts the string str1 before the nth character of the string str2, the result is in str2; {The str2 in this procedure is a variable parameter with an incoming outgoing function};

(4) Delete (str,n,m) starts from the nth of the string str, removes the M characters, and the remaining characters are in Str, {The STR in this procedure is a variable parameter and has an incoming outgoing function};

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Functions (characters and strings)