如何要求 NUMBER ONLY 用户输入

如何解决如何要求 NUMBER ONLY 用户输入

所以我正在尝试制作一个菜单循环。 一切正常。 数字 1、2 和 3 都是选项。

但我想更进一步，让程序向用户询问一个数字 如果输入了字母/字符。

问题是，我遇到了一个奇怪的无限循环。 （我知道这看起来不对，我不知道从哪里开始。感谢您的帮助！）

int menuchoice; // Menu selection for user input.
int chips = 2000;
int earned = 0;

cout << "Enter a number to select: \n";
    cin >> menuchoice;

while (menuchoice > 0 || menuchoice < 4)
    {
        if (menuchoice == 1) { // Play Slots menu where credits + amount of bet player wants to play is added.
            cout << "===============================\n";
            cout << "Enter amount you want to bet \n";
            cin >> place_bet; // check for legality in menu 2 (not made yet)

        };
        if  (menuchoice == 2) {
            cout << "Thank you for playing !!! " << name << endl;
            break;
            // exit menu displaying "THANK YOU,press any key to exit.
        };
        if  (menuchoice == 3) {

            cout << "Your chips $" << chips << endl;
            cout << "Chips earned $" << earned << endl;
            cout << "\n";
            cout << "Enter a valid number from 1 to 3 to select: \n";
            cin >> menuchoice;
        };
        if ( menuchoice >= 4 ) {
            cout << "Enter a valid number from 1 to 3\nin order to select a menu option: \n";
            cin >> menuchoice;
        };
        if (menuchoice == 0) {
            cout << "Enter a valid number from 1 to 3\nin order to select a menu option: \n";
            cin >> menuchoice;
        };
        if (menuchoice != menuchoice) {
            cout << "Enter a valid number from 1 to 3\nin order to select a menu option: \n";
            cin >> menuchoice;

        }

```