C++ Tutorial/Data Types/char functions
Содержание
iscntrl
<source lang="cpp">#include <iostream> using std::cout; using std::endl;
- include <cctype>
using std::iscntrl; using std::isgraph; using std::isprint; using std::ispunct; using std::isspace; int main() {
cout << "\nAccording to iscntrl:\nNewline "
<< ( iscntrl( "\n" ) ? "is a" : "is not a" )
<< " control character\n"
<< ( iscntrl( "$" ) ? "$ is a" : "$ is not a" )
<< " control character\n";
return 0;
}</source>
According to iscntrl: Newline is a control character $ is not a control character
isgraph
<source lang="cpp">#include <iostream> using std::cout; using std::endl;
- include <cctype>
using std::iscntrl; using std::isgraph; using std::isprint; using std::ispunct; using std::isspace; int main() {
cout << "\nAccording to isgraph:\n"
<< ( isgraph( "Q" ) ? "Q is a" : "Q is not a" )
<< " printing character other than a space\nSpace "
<< ( isgraph(" ") ? "is a" : "is not a" )
<< " printing character other than a space" << endl;
return 0;
}</source>
According to isgraph: Q is a printing character other than a space Space is not a printing character other than a space
islower
<source lang="cpp">#include <iostream> using std::cout; using std::endl;
- include <cctype>
using std::islower; using std::isupper; using std::tolower; using std::toupper; int main() {
cout << "According to islower:\n"
<< ( islower( "p" ) ? "p is a" : "p is not a" )
<< " lowercase letter\n"
<< ( islower( "P" ) ? "P is a" : "P is not a" )
<< " lowercase letter\n"
<< ( islower( "5" ) ? "5 is a" : "5 is not a" )
<< " lowercase letter\n"
<< ( islower( "!" ) ? "! is a" : "! is not a" )
<< " lowercase letter\n";
return 0;
}</source>
According to islower: p is a lowercase letter P is not a lowercase letter 5 is not a lowercase letter ! is not a lowercase letter
isprint
<source lang="cpp">#include <iostream> using std::cout; using std::endl;
- include <cctype>
using std::iscntrl; using std::isgraph; using std::isprint; using std::ispunct; using std::isspace; int main() {
cout << "\nAccording to isprint:\n"
<< ( isprint( "$" ) ? "$ is a" : "$ is not a" )
<< " printing character\nAlert "
<< ( isprint( "\a" ) ? "is a" : "is not a" )
<< " printing character\nSpace "
<< ( isprint( " " ) ? "is a" : "is not a" )
<< " printing character\n";
return 0;
}</source>
According to isprint: $ is a printing character Alert is not a printing character Space is a printing character
ispunct
<source lang="cpp">#include <iostream> using std::cout; using std::endl;
- include <cctype>
using std::iscntrl; using std::isgraph; using std::isprint; using std::ispunct; using std::isspace; int main() {
cout << "\nAccording to ispunct:\n"
<< ( ispunct( ";" ) ? "; is a" : "; is not a" )
<< " punctuation character\n"
<< ( ispunct( "Y" ) ? "Y is a" : "Y is not a" )
<< " punctuation character\n"
<< ( ispunct("#") ? "# is a" : "# is not a" )
<< " punctuation character\n";
return 0;
}</source>
According to ispunct: ; is a punctuation character Y is not a punctuation character # is a punctuation character
isspace
<source lang="cpp">#include <iostream> using std::cout; using std::endl;
- include <cctype>
using std::iscntrl; using std::isgraph; using std::isprint; using std::ispunct; using std::isspace; int main() {
cout << "According to isspace:\nNewline "
<< ( isspace( "\n" ) ? "is a" : "is not a" )
<< " whitespace character\nHorizontal tab "
<< ( isspace( "\t" ) ? "is a" : "is not a" )
<< " whitespace character\n"
<< ( isspace( " is a" : " is not a" )
<< " whitespace character\n";
return 0;
}</source>
According to isspace: Newline is a whitespace character Horizontal tab is a whitespace character % is not a whitespace character
isupper
<source lang="cpp">#include <iostream> using std::cout; using std::endl;
- include <cctype>
using std::islower; using std::isupper; using std::tolower; using std::toupper; int main() {
cout << "\nAccording to isupper:\n"
<< ( isupper( "D" ) ? "D is an" : "D is not an" )
<< " uppercase letter\n"
<< ( isupper( "d" ) ? "d is an" : "d is not an" )
<< " uppercase letter\n"
<< ( isupper( "8" ) ? "8 is an" : "8 is not an" )
<< " uppercase letter\n"
<< ( isupper("$") ? "$ is an" : "$ is not an" )
<< " uppercase letter\n";
return 0;
}</source>
According to isupper: D is an uppercase letter d is not an uppercase letter 8 is not an uppercase letter $ is not an uppercase letter
toupper and tolower
<source lang="cpp">#include <iostream> using std::cout; using std::endl;
- include <cctype>
using std::islower; using std::isupper; using std::tolower; using std::toupper; int main() {
cout << "\nu converted to uppercase is "
<< static_cast< char >( toupper( "u" ) )
<< "\n7 converted to uppercase is "
<< static_cast< char >( toupper( "7" ) )
<< "\n$ converted to uppercase is "
<< static_cast< char >( toupper( "$" ) )
<< "\nL converted to lowercase is "
<< static_cast< char >( tolower( "L" ) ) << endl;
return 0;
}</source>
u converted to uppercase is U 7 converted to uppercase is 7 $ converted to uppercase is $ L converted to lowercase is l
Using functions isalnum
<source lang="cpp">#include <iostream> using std::cout; using std::endl;
- include <cctype>
using std::isalnum; using std::isalpha; using std::isdigit; using std::isxdigit; int main() {
cout << "\nAccording to isalnum:\n"
<< ( isalnum( "A" ) ? "A is a" : "A is not a" )
<< " digit or a letter\n"
<< ( isalnum( "8" ) ? "8 is a" : "8 is not a" )
<< " digit or a letter\n"
<< ( isalnum( "#" ) ? "# is a" : "# is not a" )
<< " digit or a letter\n";
return 0;
}</source>
According to isalnum: A is a digit or a letter 8 is a digit or a letter # is not a digit or a letter
Using functions isalpha
<source lang="cpp">#include <iostream> using std::cout; using std::endl;
- include <cctype>
using std::isalnum; using std::isalpha; using std::isdigit; using std::isxdigit; int main() {
cout << "\nAccording to isalpha:\n"
<< ( isalpha( "A" ) ? "A is a" : "A is not a" ) << " letter\n"
<< ( isalpha( "b" ) ? "b is a" : "b is not a" ) << " letter\n"
<< ( isalpha( "&" ) ? "& is a" : "& is not a" ) << " letter\n"
<< ( isalpha( "4" ) ? "4 is a" : "4 is not a" ) << " letter\n";
return 0;
}</source>
According to isalpha: A is a letter b is a letter & is not a letter 4 is not a letter
Using functions isdigit
<source lang="cpp">#include <iostream> using std::cout; using std::endl;
- include <cctype>
using std::isalnum; using std::isalpha; using std::isdigit; using std::isxdigit; int main() {
cout << "According to isdigit:\n"
<< ( isdigit( "8" ) ? "8 is a" : "8 is not a" ) << " digit\n"
<< ( isdigit( "#" ) ? "# is a" : "# is not a" ) << " digit\n";
return 0;
}</source>
According to isdigit: 8 is a digit # is not a digit
Using functions isxdigit
<source lang="cpp">#include <iostream> using std::cout; using std::endl;
- include <cctype>
using std::isalnum; using std::isalpha; using std::isdigit; using std::isxdigit; int main() {
cout << "\nAccording to isxdigit:\n"
<< ( isxdigit( "F" ) ? "F is a" : "F is not a" )
<< " hexadecimal digit\n"
<< ( isxdigit( "J" ) ? "J is a" : "J is not a" )
<< " hexadecimal digit\n"
<< ( isxdigit( "7" ) ? "7 is a" : "7 is not a" )
<< " hexadecimal digit\n"
<< ( isxdigit( "$" ) ? "$ is a" : "$ is not a" )
<< " hexadecimal digit\n"
<< ( isxdigit( "f" ) ? "f is a" : "f is not a" )
<< " hexadecimal digit" << endl;
return 0;
}</source>
According to isxdigit: F is a hexadecimal digit J is not a hexadecimal digit 7 is a hexadecimal digit $ is not a hexadecimal digit f is a hexadecimal digit
Using strrchr: index a character in a string
<source lang="cpp">#include <iostream>
- include <string.h>
using namespace std; int main() {
char *string1 = "this is a test";
int c = "t";
cout << "last occurrence of character "" << (char) c
<< "" is: \"" << strrchr( string1, c ) << "\"" << endl;
return 0;
}</source>
