Question

I would have expected the following C# program to only print “EOF!” once I hit “Ctrl-Z” in the console.
Instead, the program finishes as soon as I hit Enter:

var textReader = Console.In;
var sb = new StringBuilder();
while(textReader.Peek() != -1)
{
    sb.Append((char)textReader.Read());
}
Console.WriteLine("Entered: '{0}'", sb);
Console.WriteLine("EOF!");

Example:

12345 <= I entered this
Entered: '12345 <= program outputs this
'
EOF!
Press any key to continue . . .

Can anyone explain the above behaviour? It’s not at all what I expected.

How can I read more than 1 line of input from Console.In one character at a time?

Update: As answered below: The issue is that Peek() can’t be relied on. Using Read() works though.

Answer 1

Console.In.Read() returns -1 on EOF, So you can do this:

int c;
while((c = Console.In.Read()) != -1)
Console.Out.Write((char)c);