function
<cctype>
toupper
Convert lowercase letter to uppercase
Converts c to its uppercase equivalent if c is a lowercase letter and has an uppercase equivalent. If no such conversion is possible, the value returned is c unchanged.
Notice that what is considered a letter may depend on the locale being used; In the default "C" locale, a lowercase letter is any of: a b c d e f g h i j k l m n o p q r s t u v w x y z, which translate respectively to: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z.
In other locales, if a lowercase character has more than one correspondent uppercase character, this function always returns the same character for the same value of c.
In C++, a locale-specific template version of this function (toupper) exists in header <locale>.
Parameters
- c
- Character to be converted, casted to an int, or EOF.
Return Value
The uppercase equivalent to c, if such value exists, or c (unchanged) otherwise. The value is returned as an int value that can be implicitly casted to char.
Example
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| /* toupper example */ #include <stdio.h> #include <ctype.h> int main () { int i=0; char str[]="Test String.\n"; char c; while (str[i]) { c=str[i]; putchar (toupper(c)); i++; } return 0; }
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Output:
See also
- tolower
- Convert uppercase letter to lowercase (function)
- islower
- Check if character is lowercase letter (function)
- isupper
- Check if character is uppercase letter (function)
- isalpha
- Check if character is alphabetic (function)