isalnum


function template
<locale> 
template <class charT>
  bool isalnum ( charT c, const locale& loc );

Check if character is alphanumeric using locale

Checks whether c is an alphanumeric character using ctype facet of locale loc, returning the same as a call to:

  
use_facet < ctype<charT> > (loc).is (ctype_base::alnum, c)


This function replicates the functionality of its C-library equivalent isalnum. See isalnum for more info.

Parameters

c
Character to be checked.
loc
Locale to be used. Shall have facet ctype present.


Template parameter charT is the character type.

Return Value

true if indeed c is an alphanumeric character, false otherwise.

Example

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// isalnum example (C++)
#include <iostream>
#include <string>
#include <locale>
using namespace std;

int main ()
{
  locale loc;
  string str = "c3po...";
  size_t i=0;
  while ( (i<str.length()) && (isalnum(str[i])) ) {++i;}
  cout << "The first " << i << " characters are alphanumeric.\n";
  return 0;
}


Output:

The first 4 characters are alphanumeric.


See also

ctype Character type facet (class template)
isalnum (cctype) Check if character is alphanumeric (function)
isalpha Check if character is alphabetic using locale (function template)
isdigit Check if character is a decimal digit using locale (function template)