isdigit


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

Check if character is a decimal digit using locale

Checks whether c is a decimal digit using ctype facet of locale loc, returning the same as a call to:

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


This function replicates the functionality of its C-library equivalent isdigit. See isdigit 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 a decimal digit character, false otherwise.

Example

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

int main ()
{
  locale loc;
  string str="1776ad";
  if ( isdigit(str[0],loc) )
  {
    int year;
    stringstream(str) >> year;
    cout << "The year that followed " << year << " was " << (year+1) << ".\n";
  }
  return 0;
}


Output:

The year that followed 1776 was 1777.


See also