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Syntax Question: Reading from MySQL database

Posted on 2004-11-01
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Last Modified: 2010-04-24
I working with a MYSQL database, using C++ .NET. The program compiles, and outputs data to the console, using a line such as this:

Console::WriteLine("{0}", reader->Item[S"age"]);

However, I want to do more than just display the "age" to the console, I want to do calculations on the data. So, how do I convert the infomation to an Integer? I've tried variations of "Int32::Parse", ".ToString", "Int32::ToInt32" etc., but can't get the right syntax.
Please help. Thank You.
0
Question by:KellyJensen
    4 Comments
     
    LVL 48

    Accepted Solution

    by:
    int n = Int32::Parse(reader->Item[S"age"]->ToString());
    0
     

    Author Comment

    by:KellyJensen
    AlexFM, thank you for your answer.  It compiles and runs, but after an incredible amount of grinding away, this error message pops up:

    Microsoft Development Environment
    An unhandled exception of type 'System.FormatException' occurred in mscorlib.dll.
    Additional information: Input string was not in correct format.

    Any other suggestions?
    0
     
    LVL 48

    Expert Comment

    by:AlexFM
    Possibly in most records database field contains valid number in the age field. But some records may contain, for example NULL or other invalid value - you can see this in your current program version. You need to handle exception:

    int n;

    try
    {
        n = Int32::Parse(reader->Item[S"age"]->ToString());
    }
    catch ( System.FormatException ex )
    {
        // handle error here - for example, show message, set n to 0 etc.
    }
    0
     

    Author Comment

    by:KellyJensen
    Thank you so very much, there was a glitch in my database. Your answer was very correct.
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