File stream reading line with specific criteria

Gimmicky (3)
classA, (-7, 11) // classA requires 2 variables(x,y)
classB, (5, -31, -22) // classB requires 3 variables(x,y,z)
classC, (-7, 11), (20, -1) // classC requires 4 variables in the described format(x1,y1,x2,y2)


Assuming the above text file data,
How would I go about extracting the integer values to construct the class object itself?

Rough idea 
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ifstream infile;
string classType,rubbish;
string x,y,z;

while(getline(infile,classType,','))
{
 if (classType == "classA")
   {
       // do specific format input stream and stoi conversion
       getline(infile,rubbish,'(');
       getline(infile,x,',');
       getline(infile,rubbish,' ');
       getline(infile,y,')');
       ClassA aObj(stoi(x),stoi(y));
   }
 else if (classType == "classB")
   {
       // do specific format input stream and stoi conversion
       getline(infile,rubbish,'(');
       getline(infile,x,',');
       getline(infile,rubbish,' ');
       getline(infile,y,',');
       getline(infile,rubbish,' ');
       getline(infile,z,')');
   }
 else if (classType == "classC")
   {
       // do specific format input stream and stoi conversion

   }
}
Last edited on
ne555 (10692)
> Assuming the above text file data,
¿the comments are also part of the input file?

> code below doesnt work
it's commented, that's why it does nothing
if you uncomment it it will work (extract the x, y values)

If you do not observe that behaviour, you need to be clearer with your issue, ¿how does it now work?
I suppose that you didn't try to use `aObj' outside of the if scope.
Gimmicky (3)
Sorry for not clarifying earlier. It works for the first loop and creates the object of class A but as it goes onto the second loop, the value of classType is changed to "classB" but it does not enter the conditional if statement preventing the object of class B to be created.

The program is supposed to retrieve data for different classes displayed in a specific format. As the loop runs,within each if statement, the object is instantiated and stored in a vector to be implemented later.
Last edited on
JLBorges (13770)
After reading the data for a particular line, extract and discard the rest of that line.
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if (classType == "classA")
   {
       // do specific format input stream and stoi conversion
       getline(infile,rubbish,'(');
       getline(infile,x,',');
       getline(infile,rubbish,' ');
       getline(infile,y,')');
       ClassA aObj(stoi(x),stoi(y));

       infile.ignore( 1000000, '\n' ) ; // throw the rest of this line away 
   }
   // etc.


You may want to check for input errors; ie. handle badly formed lines.
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