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getline failing to read from data file?

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Join Date: Aug 2007

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vmanes

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Re: getline failing to read from data file?

#11

Apr 14th, 2008

n8makar - congratulations on finding your own solution. I'm surprised the others who responded didn't spot that.

Mixing input with the extraction operator ( >> ) and getlline is a frequent source of problems for beginning students, that left over newline causes no end of frustration.

Now consider what happens if data is like:

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
12345   This is the name of the thing
8765  Some other thing
12345   This is the name of the thing
8765  Some other thing

Your use of fin.ignore( ) will throw away the data we actually want.
An alternative means of removing the whitespace (blanks, tabs, newlines) is the ws manipulator. You might use it like:

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
fin >> num_var;
fin >> ws;  //eats up whitspace till displayable char
getline( fin, string_var );
fin >> num_var;
fin >> ws;  //eats up whitspace till displayable char
getline( fin, string_var );

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