getinputcpp/example.cpp at main · Cthuloops/getinputcpp · GitHub

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// getinputcpp is a header file that is used for simple input validation

#include<iostream>
#include<sstream>
#include"./getinputcpp.hpp"


voidprint_main_menu();
voidclear_input_example();
voidinteractive_clear_input_example();
voidget_input_example();
voidinteractive_get_input_example();


intmain() {
int choice = 0;
bool keep_going = true;
while (keep_going) {
print_main_menu();
 std::cin >> choice;
clear_input(std::cin);
switch (choice) {
case1:
clear_input_example();
break;
case2:
interactive_clear_input_example();
break;
case3:
get_input_example();
break;
case4:
interactive_get_input_example();
break;
case5:
 keep_going = false;
break;
 }
 }
return0;
}


voidprint_main_menu() {
 std::cout << "\n+----------------------| Main Menu |-----------------------+\n"
 << "|----------------------------------------------------------|\n"
 << "| 1. clear_input example |\n"
 << "| 2. interactive clear_input example |\n"
 << "| 3. get_input example |\n"
 << "| 4. interactive get_input |\n"
 << "| 5. quit |\n"
 << "+----------------------------------------------------------+\n"
 << "Select an option: ";
}


voidclear_input_example() {
 std::cout << "\n+----------------| Clear Input Example |-------------------+\n"
 << "| Initializing variable user_int for storing user input |\n"
 << "| Simulating user input of \"12\\n\" |\n";
int user_int;
 std::istringstream input("12\n");
 input >> user_int;
 std::cout << "| user_int is: " << user_int
 << " after reading into the variable. |\n"
 << "| This leaves the \\n in the input buffer which we can see |\n"
 << "| using peek(): " << input.peek() << ", which is the ASCII character for LF. |\n"
 << "| LF is the control character for newline on Linux. |\n";
clear_input(input);
if (input.peek() == EOF) {
 std::cout << "| After calling clear_input on the input buffer, it now |\n"
 << "| reads EOF or end of file. |\n"
 << "+----------------------------------------------------------+\n";
 }
}


voidinteractive_clear_input_example() {
 std::cout << "\n+-----------| Interactive Clear Input Example|-------------+\n"
 << "|----------------------------------------------------------|\n"
 << "| Your input is going to get stored as an int in user_int. |\n"
 << "| Try entering whatever you like, -1 is to exit. |\n"
 << "| Enter some additional text after the -1 to see how the |\n"
 << "| clear_input function clears the buffer. |\n"
 << "+----------------------------------------------------------+\n"
 << "Enter: ";
int user_int;
const std::string prompt = "Try entering anything you like (-1 to exit): ";
 std::cin >> user_int;
while (std::cin.fail() || user_int != -1) {
clear_input(std::cin);
 std::cout << prompt;
 std::cin >> user_int;
 }
 std::string remainder = "";
getline(std::cin, remainder);
if (remainder.size() > 38) {
 remainder = remainder.substr(0, 38) + "...";
 }
 std::cout << "You entered -1 and"
 << (remainder.size() != 0 ? remainder : "\\n") << "\n"
 << "Calling clear_input removes everything after the -1 and\n"
 << "leaves a clear buffer for the next cin, getline, or\n"
 << "get_input call\n";
}


voidget_input_example() {
 std::cout << "\n+------------------| Get Input Example |------------------+\n"
 << "|----------------------------------------------------------|\n"
 << "| Initializing user_double for storing input and |\n"
 << "| simulating user input of \"1.35\\n\". |\n";
double user_double;
 std::istringstream input("1.35\n");
 user_double = get_input<double>(input, "");
 std::cout << "| The value in user_double is: " << user_double;
if (input.peek() == EOF) {
 std::cout << " and there's nothing |\n"
 << "| left in the input buffer |\n"
 << "+----------------------------------------------------------+\n";
 }
}


voidinteractive_get_input_example() {
 std::cout << "\n+-------------| Interactive Get Input Example |------------+\n"
 << "| Your input is going to be stored as a double |\n"
 << "| Try entering whatever you like, get_input has basic |\n"
 << "| validation built in to make sure the correct type of |\n"
 << "| input is acquired, it also leaves nothing in the buffer. |\n"
 << "+-----------------------------------------------------------+\n";
double user_double = get_input<double>(std::cin, "Enter a double: ");
}