Function to make output lowercase or uppercase wont run

[trannghi7707]

Hi there,
my program supposed to convert output to either uppcase or lowercase and count commas and consonants.
My code can run but when I do cout in the main function, the lower and upper function wont do anything.
here's my attempt.

  #include <iostream>
#include <fstream>
#include <string>
#include <cctype>

using namespace std;

int CountCommas(char m[])
{
	int commas = 0;
	for (int i = 0; i < strlen(m); i++)
	{
		if (m[i] == ',')
			commas++;
		else;
	}
	return commas;
}
int CountCons(char m[])
{
	int cons = 0;
	for (int i = 0; i < strlen(m); i++)
	{
		if (m[i] == 'a' || m[i] == 'o' || m[i] == 'e' || m[i] == 'i' || m[i] == 'u' ||
			m[i] == 'A' || m[i] == 'O' || m[i] == 'E' || m[i] == 'I' || m[i] == 'U');
		else if (m[i] >= 'a' && m[i] <= 'z' || m[i] >= 'A' && m[i] <= 'Z')
			cons++;
	}
	return cons;
}
void ConvToUp(char m[])
{
	for (int i = 0; i < strlen(m); i++)
		toupper(m[i]);
}
void ConvToLo(char m[])
{
	for (int i = 0; i < strlen(m); i++)
		tolower(m[i]);	
}
int main()
{
	char fn[80];
	int cons = 0, commas = 0, choice;
	cout << "Please enter file name: ";
	cin >> fn;
	cout << "Input 1 for lower case output and 2 for upper case output" << endl;
	cin >> choice;
	ifstream infile(fn);
	if (!infile) cout << "Invalid file" << endl;
	else
	{
		char line[80];
		while (infile.getline(line, 80))
		{
			
			if (choice == 1)
			{	
				ConvToLo(line);
			}
			else if (choice == 2)
			{	
				ConvToUp(line);
			}
			cout << line << endl;
			commas += CountCommas(line);
			cons += CountCons(line);
		}
		
		infile.close();
	}
	cout << endl;
	cout << "Commas: " << commas << endl;
	cout << "Consonant: " << cons << endl;

	return 0;
}

[deleted account xyzzy]

You are not assigning the result of tolower and toupper to the current string's element in your conversion functions.

#include <iostream>
#include <cstring>

void ConvertToUpper(char[]);

int main()
{
   char str[] { "A StRiNg" };

   ConvertToUpper(str);

   std::cout << "The string is: " << str << '\n';
}

void ConvertToUpper(char str[])
{
   for (int i = 0; i < strlen(str); i++)
   {
      str[i] = toupper(str[i]);
   }
}

The string is: A STRING

[trannghi7707]

wow, i see, thank you very much.