这实际上与我提出的另一个问题有关，但我已经缩小了问题并重新编写了程序，以便更清洁，更准确。
主要功能将用户传递到菜单，在菜单中他们可以选择他们想要做的事情。问题是，每次按下返回键时，它似乎都会将输入记录到cin缓冲区中。当用户最终做出选择并被传递给适当的函数时，它会吐出所有输入的键，这会导致它跳过整个过程。这非常烦人，特别是因为我想使用VK_RETURN进行选择。
现在，我可以随处可见一堆cin.clear（）和cin.ignore（），但据我所知，这是不好的做法。此外，它与程序混淆，因为它强制用户点击输入键一个额外的时间来下线，并混乱格式化。
有没有解决的办法？或者是cin.clear（）和cin.ignore我唯一的希望？
main.cpp中
#include <limits>
#include <iostream>
#include "menu_GUI.h"
int main()
{
bool running = true;
std::string selection; //user selection for selector menu
std::string address; //address to send funds to
int amount; //amount of funds to send
std::string password; //password for wallet encryption
menu_GUI menu; //object for menu_GUI class
while(running)
{
selection = menu.mainMenu(); //collect users selection from the menu_GUI class selector function
if(selection == "send")
{
address = menu.askAddress(address); //collects the address the user wants to send funds to
if(address != "cancel"){amount = menu.askAmount(amount);} //collects the amount the user wants to send if they don't cancel
if(amount != 0){} //if the amount isn't 0, then it sends the transaction (unfinished, does nothing right now)
}
if(selection == "lock") //unfinished, but will lock the wallet
{
}
if(selection == "unlock") //unfinished, but will lock the wallet
{
}
}
return 0;
}
menu_GUI.h
#ifndef MENU_GUI_H
#define MENU_GUI_H
#include <vector>
#include <string>
class menu_GUI
{
public:
std::string mainMenu();
std::string askAddress(std::string address);
int askAmount(int amount);
void moveCursor(int x, int y);
void hideCursor();
private:
std::vector<std::string> UI {"[Send] ", "Lock ", "Unlock"};
int rightMoves = 2;
int leftMoves;
int inputDelay = 150; //modify this value to change the delay between user selector movements
std::string selection;
};
#endif // MENU_GUI_H
menu_GUI.cpp
#include "menu_GUI.h"
#include <windows.h>
#include <iostream>
#include <limits>
std::string menu_GUI::mainMenu()
{
bool selecting = true;
while(selecting)
{
hideCursor(); //hides the cursor
leftMoves = 2 - rightMoves; //sets the number of left movements remaining based on right movements remaining
for(int x = 0, y = 0; x < UI.size(); x++)
{
moveCursor(0, 0);
std::cout << "Balance: "; //displays users balance
moveCursor(0, 2);
std::cout << "Address: "; //displays users public key
moveCursor(y, 4); //prints out the map
std::cout << UI[x];
y += UI[x].length(); //sets y equal to the total length accumulated on the line so far
}
if(GetAsyncKeyState(VK_RIGHT)) //handles right key inputs
{
if(rightMoves != 0) //check if user can move right
{
switch(rightMoves)
{
case 1:
rightMoves--;
UI[1] = "Lock ";
UI[2] = "[Unlock]";
break;
//modifies the UI vector accordingly
case 2:
rightMoves--;
UI[0] = "Send ";
UI[1] = "[Lock] ";
break;
default:
break;
}
}
Sleep(inputDelay); //Delay, so that user doesn't input twice
}
if(GetAsyncKeyState(VK_LEFT)) //handles right key inputs
{
if(leftMoves != 0) //check if user can move left
{
switch(leftMoves)
{
case 1:
rightMoves++;
UI[0] = "[Send] ";
UI[1] = "Lock ";
break;
//modifies the UI vector accordingly
case 2:
rightMoves++;
UI[1] = "[Lock] ";
UI[2] = "Unlock";
break;
default:
break;
}
}
Sleep(inputDelay); //Delay, so that user doesn't input twice
}
if(GetAsyncKeyState(VK_RETURN)) //handles which selection the user chooses based on how many rightMoves remaining
{
system("cls"); //clears the screen, since it's about to display a new page
switch(rightMoves)
{
case 2:
selection = "send";
return (selection);
break;
case 1:
selection = "lock";
return (selection);
break;
case 0:
selection = "unlock";
return (selection);
break;
default:
break;
}
}
}
}
std::string menu_GUI::askAddress(std::string address) //asks user where they wanna send it
{
std::cout << "Enter where you wanna send the BigBoiCoins. Or type cancel." << std::endl;
std::cout << "Address: ";
getline(std::cin, address); //shouldn't need to check failbit. user input can be anything.
return address;
}
int menu_GUI::askAmount(int amount) //asks user how much they wanna send
{
bool inputting = true;
while(inputting)
{
std::cout << "Enter how many BigBoiCoins you wanna send. Just put 0 if you don't wanna send any." << std::endl;
std::cout << "Amount: ";
std::cin >> amount;
if(!std::cin) //checks failbit to make sure user isn't an idiot and inputs something other than a number
{
std::cin.clear();
std::cin.ignore(std::numeric_limits<std::streamsize>::max(), '\n');
std::cout << "who buckaroo! That wasn't a good input. I'll let you try again, I know some of us are special." << std::endl;
}
else{inputting = false;}
}
return amount;
}
void menu_GUI::moveCursor(int x, int y) //move the cursor to the desired coords
{
static const HANDLE hOut = GetStdHandle(STD_OUTPUT_HANDLE);
std::cout.flush();
COORD coord = { (SHORT)x, (SHORT)y };
SetConsoleCursorPosition(hOut, coord);
}
void menu_GUI::hideCursor() //hides the cursor
{
CONSOLE_CURSOR_INFO info;
info.dwSize = 100;
info.bVisible = false;
SetConsoleCursorInfo(GetStdHandle(STD_OUTPUT_HANDLE), &info);
}
你需要添加一些输入函数来“吃掉”一些字符。你最好用if(GetAsyncKeyState(KEY) & 0x8000)代替。
if (GetAsyncKeyState(VK_RETURN)& 0x8000) //handles which selection the user chooses based on how many rightMoves remaining
{
getline(std::cin,NULL);
//...
}
和
std::cin >> amount;
char c = getchar();//eat '\n'