Programming

int ToLower(string my_input)
  {
         int string_length = my_input.length();
         for (int i=0; i<string_length; i++) {
    my_input[i]=tolower(my_input[i]);
      }
  return 0;
  }

nt i=0;   char str[]="Test String.\n";   char c;   while (str[i])   {     c=str[i];     putchar (tolower(c));     i++;

error: invalid conversion from ‘char’ to ‘const char*’
error:   initializing argument 1 of ‘std::basic_string<_CharT, _Traits, _Alloc>::basic_string(const _CharT*, const _Alloc&)
 [with _CharT = char, _Traits = std::char_traits<char>, _Alloc = std::allocator<char>]’

int ToLower(string my_input)
  {
         int string_length = my_input.length();
         for (int i=0; i<string_length; i++) {
// here trying to convert from int to string
my_input = (string) my_input[i];
    my_input[i]=tolower(my_input[i]);
      }
  return 0;
  }

int ToLower(string my_input)
  {
         int string_length = my_input.length();
         for (int i=0; i<string_length; i++) {
// here trying to convert from int to string
    typedef char charType; 
    charType MyChar = my_input[i];
    my_input[i]=tolower(my_input[i]);
      }
  return 0;
  }

int tolower( int );

#include <ctype.h>
#include <string>
#include <iostream>

using namespace std;

void toLowerVal( string str )
{
    for ( int ii = 0; ii < str.length(); ii++ )
    {
        str[ ii ] = ( char ) ::tolower( str[ ii ] );
    }
}

void toLowerRef( string &str )
{
    for ( int ii = 0; ii < str.length(); ii++ )
    {
        str[ ii ] = ( char ) ::tolower( str[ ii ] );
    }
}

int main( int argc, char **argv )
{
    for ( int ii = 1; ii < argc; ii++ )
    {
        string s1 = argv[ ii ];
        cout << s1 << endl;
        toLowerVal( s1 );
        cout << s1 << endl;
        toLowerRef( s1 );
        cout << s1 << endl;
    }

    return( 0 );
}

bash-3.2$ ./str ASDf as1FFFF
ASDf
ASDf
asdf
as1FFFF
as1FFFF
as1ffff

int ToLower(string my_input)
  {
         int string_length = my_input.length();
         for (int i=0; i<string_length; i++) {
    my_input[i]=char(tolower(my_input[i]));
      }
  return 0;
  }