Getline Not Working Properly? What Could Be the Reasons

getline not working properly ? What could be the reasons?

Since you have not posted any code. I am going to take a guess.

A common problem while using getline with cin is getline does not ignore leading whitespace characters.

If getline is used after cin >>, the getline() sees this newline character as leading whitespace, and it just stops reading any further.

How to resolve it?

Call cin.ignore() before calling getline()

Or

make a dummy call getline() to consume the trailing newline character from the cin >>

getline() does not work if used after some inputs

Characters are extracted until either (n - 1) characters have been
extracted or the delimiting character is found (which is delimiter if this
parameter is specified, or '\n' otherwise). The extraction also stops
if the end of the file is reached in the input sequence or if an error
occurs during the input operation.

When cin.getline() reads from the input, there is a newline character left in the input stream, so it doesn't read your c-string. Use cin.ignore() before calling getline().

cout<<"Journal Entry:\t";
cin.ignore();
cin.getline(journal,23);

NOTE:(getline was not the issue) C++ getline() stops working in user defined function but works in main function

The problem is that there is no morse code for a space.

Make a verification:

    int n = alphabet.find(userInput[i]);
    encodedEnglishText += (n == string::npos) ? "  ":  morseAlphabet[n];

Then it will work.

std::getline does not work inside a for-loop

You can see why this is failing if you output what you stored in local (which is a poor variable name, by the way :P):

#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
using namespace std;
int main()
{
    int n;
    cin >> n;
    for(int i = 0; i < n; i++)
    {
        string local;
        getline(cin, local);
        std::cout << "> " << local << std::endl;
    }

    //............................
    return 0;
}

You will see it prints a newline after > immediately after inputting your number. It then moves on to inputting the rest.

This is because getline is giving you the empty line left over from inputting your number. (It reads the number, but apparently doesn't remove the \n, so you're left with a blank line.) You need to get rid of any remaining whitespace first:

#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
using namespace std;
int main()
{
    int n;
    cin >> n;
    cin >> ws; // stream out any whitespace
    for(int i = 0; i < n; i++)
    {
        string local;
        getline(cin, local);
        std::cout << "> " << local << std::endl;
    }

    //............................
    return 0;
}

This the works as expected.

Off topic, perhaps it was only for the snippet at hand, but code tends to be more readable if you don't have using namespace std;. It defeats the purpose of namespaces. I suspect it was only for posting here, though.

getline not asking for input?

You have to be careful when mixing operator>> with getline. The problem is, when you use operator>>, the user enters their data, then presses the enter key, which puts a newline character into the input buffer. Since operator>> is whitespace delimited, the newline character is not put into the variable, and it stays in the input buffer. Then, when you call getline, a newline character is the only thing it's looking for. Since that's the first thing in the buffer, it finds what it's looking for right away, and never needs to prompt the user.

Fix:
If you're going to call getline after you use operator>>, call ignore in between, or do something else to get rid of that newline character, perhaps a dummy call to getline.

Another option, and this is along the lines of what Martin was talking about, is to not use operator>> at all, and only use getline, then convert your strings to whatever datatype you need. This has a side effect of making your code more safe and robust. I would first write a function like this:

int getInt(std::istream & is)
{
    std::string input;
    std::getline(is,input);

    // C++11 version
    return stoi(input); // throws on failure

    // C++98 version
    /*
    std::istringstream iss(input);
    int i;
    if (!(iss >> i)) {
        // handle error somehow
    }
    return i;
    */
}

You can create a similar function for floats, doubles and other things. Then when you need in int, instead of this:

cin >> i;

You do this:

i = getInt(cin);

getline statement is not getting the input

cin will leave new lines in the buffer. Therefore when you get rno from cin there is actually an \n left in the cin buffer. When you go to read the name it just grabs the \n and instantly returns.
Doing something like cin.ignore(); after the first cin should clear the buffer and allow you to correctly read the user input.

c++ getline() isn't waiting for input from console when called multiple times

The problem is you are mixing calls to getline() with the use of the operator >>.

Remember that operator >> ignored leading white space so will correctly continue across lines boundaries. But stops reading after the input has successfully been retrieved and thus will not swallow trailing '\n' characters. Thus if you use a getline() after a >> you usually get the wrong thing unless you are careful (to first remove the '\n' character that was not read).

The trick is to not use both types of input. Pick the appropriate one and stick to it.

If it is all numbers (or objects that play nice with operator >>) then just use operator >> (Note string is the only fundamental type that is not symmetric with input/output (ie does not play nicely)).

If the input contains strings or a combination of stuff that will require getline() then only use getline() and parse the number out of the string.

std::getline(std::cin, line);
std::stringstream  linestream(line);

int  value;
linestream >> value;

// Or if you have boost:
std::getline(std::cin, line);
int  value = boost::lexical_cast<int>(line);

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