用户检测到的C ++检测ENTER键 [英] C++ Detecting ENTER key pressed by user

问题描述

我有一个循环，要求用户输入名称.当用户按ENTER键.....或输入20个名称时，我需要停止.但是，当用户按下ENTER键时，我的方法不会停止

I have a loop where I ask the user to enter a name. I need to stop when the user presses the ENTER key..... or when 20 names have been entered. However my method doesn't stop when the user presses the ENTER key

//loop until ENTER key is entered or 20 elements have been added
bool stop = false;
int ind = 0;
while( !stop || ind >= 20 ){

    cout << "Enter name #" << (ind+1) << ":";
    string temp;
    getline(cin, temp);
    int enterKey = atoi(temp.c_str());        

    if(enterKey == '\n'){
        stop = true;            
    }
    else{
        names[ind] = temp;
    }

    ind++;


}

推荐答案

您可以使用atoi将读取的字符串转换为整数:

You convert the read string to an integer with atoi:

int enterKey = atoi(temp.c_str());        

如果temp是类似于"1234"的字符串，这会将enterKey设置为1234.然后，将enterKey与\n的ASCII值进行比较.这很可能没有做任何有用的事情.

If temp is a string like "1234" this will set enterKey to 1234. Then you compare enterKey to the ASCII value of \n. This is most probably not doing anything useful.

也std::getline只是读取直到(但不包括)下一个'\n'的字符.如果用户仅按Enter键而不输入任何其他字符，则std::getline将返回一个空字符串.如果字符串为空，可以使用其empty()方法轻松测试:

Also std::getline just read the characters up to, but not including, the next '\n'. If a user just presses enter without typing any other characters, std::getline will return an empty string. If a string is empty can be easily tested with its empty() method:

getline(cin, temp);
if (temp.empty()) {
  stop = true;
}

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