C++ Programming/Code/Standard C Library/Functions/isalnum

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isalnum[edit]

Syntax
#include <cctype>
int isalnum( int ch );

The function isalnum() returns non-zero if its argument is a numeric digit or a letter of the alphabet. Otherwise, zero is returned.

char c;
scanf( "%c", &c );
if( isalnum(c) )
  printf( "You entered the alphanumeric character %c\n", c );
Related topics
isalpha - iscntrl - isdigit - isgraph - isprint - ispunct - isspace - isxdigit