title: C++ Creating & Using Class
body: <p>I have to create a class for an assignment, I've done all that I can &amp; I've done the research and I have read my textbook. What else do I need to do to my classes to make what is in my Main run? Everything you need to know is in the code description.</p>
  
  <pre><code>/*  LAB07.cpp
      ALEXANDER YHAP
      04/2012
  
      In this lab you will create a new class called LabMetaData. Objects of this
      class could be used in future lab assignments to store information about 
      the lab itself. 
  
      An object of class LabMetaData has the following attributes:
      .   Lab Number - A whole, positive number. Zero is valid.
      .   Lab Title - A title for the Lab Assignment
      .   Lab Author - The name of the programmer that wrote the lab.
      .   Lab Data - The date the lab was written, stored as three integer 
          numbers. The Day must be between 1 and 31. The month must be between 1 
          and 12. The year must be 4 digits and in the 21st Century (between 2000 
          and 2099).
      .   Lab Description - A description of the Lab Assignment.
  
      An object of class LabMetaData has the following methods:
      .   Constructor - set the Lab Number to zero, the Lab date to 1/1/2010, 
          and all other attributes to empty strings. (Hint: call the SetData() 
          from the constructor function to avoid duplicating your code)
      .   SetData() - sets the attributes of the object to the parameters as long 
          as the parameters are valid. Rules: 
          o   ALL of the parameters must be valid in order for ANY of the 
              attributes to change. 
          o   Validation rules are explained above for Lab Number and Lab Date. 
              Title, Author, and Description have no validation.
          o   If no problems are detected, return TRUE. Otherwise return FALSE.
      .   ShowData() - displays all the object's attributes on the console. 
  
      The main() function and a sample executable is provided. 
  */
  
  #include &lt;iostream&gt;
  using namespace std;
  //Class Declaration Section
  class LabMetaData 
  {
      private:
      int labNum;
      string labTitle;
      string labAuthor;
      int Month;
      int Day;
      int Year;
      string labDesc;    
  
      public:    
  //    LabMetaData(int labNum, string labTitle, string labAuthor,int Month, int Day, int Year, string labDesc); //constructor
      LabMetaData(int = 0, string = "Empty Title", string = "Empty Author",int = 01, int = 01, int = 2012, string = "Empty Description");
      void LabMetaData::SetData(int, string, string, int, int, int, string);
      void LabMetaData::ShowData();
  };
  //Class Implementation Section
  LabMetaData::LabMetaData(int Num, string Title, string Author, int MM, int DD, int YYYY, string Desc)
  {
      labNum = Num;
      labTitle = Title;
      labAuthor = Author;
      Month = MM;
      Day = DD;
      Year = YYYY;
      labDesc = Desc;
  }
  
  void LabMetaData::SetData(int Num, string Title, string Author, int MM, int DD, int YYYY, string Desc)
  {
  //    labNum = 7;
  //    labTitle = "N/A";
  //    labAuthor = "Unknown";
  //    Month = 01;
  //    Day = 01;
  //    Year = 2012;
  //    labDesc = "N/A";
  //    return;
      labNum = Num;
      labTitle = Title;
      labAuthor = Author;
      Month = MM;
      Day = DD;
      Year = YYYY;
      labDesc = Desc;
      return;
  }
  
  void LabMetaData::ShowData()
  {
       cout &lt;&lt; "Lab " &lt;&lt; labNum &lt;&lt; ": " &lt;&lt; labTitle &lt;&lt; endl;
       cout &lt;&lt; "Created by: " &lt;&lt; labAuthor &lt;&lt; endl;
       cout &lt;&lt; "Date: " &lt;&lt; Month &lt;&lt; "/" &lt;&lt; Day &lt;&lt; "/" &lt;&lt; Year &lt;&lt; endl;
       cout &lt;&lt; "Description: " &lt;&lt; labDesc &lt;&lt; endl;
       cout &lt;&lt; endl;
  
       return;
  }
  
  int main()
  {
  
      LabMetaData Lab7; 
  
      cout &lt;&lt; endl &lt;&lt; "Uninitialized: " &lt;&lt; endl;
      Lab7.ShowData();
  
      Lab7.SetData(7,
      "Introduction to Classes",
      "Alexander Yhap",
      10, 3, 2010,
      "In this lab you will create a new class called LabMetaData. Objects of this class could be used in future lab assignments to store information about the lab itself.");
  
      cout &lt;&lt; endl &lt;&lt; "Intialized: " &lt;&lt; endl;
      Lab7.ShowData();
  
      if(!Lab7.SetData(-1, "Test", "Test", 13, 32, 11, "Causing Errors"))
          cout &lt;&lt; "\nErrors!" &lt;&lt; endl;
  
      cout &lt;&lt; endl &lt;&lt; "After Invalid Modification Attempt: " &lt;&lt; endl;
      Lab7.ShowData();
  
      cout &lt;&lt; endl &lt;&lt; endl;
      system("pause");
      return 0;
  }
  </code></pre>
  
  <hr>
  
  <p>The error messages are:</p>
  
  <pre><code>prog.cpp:32:27: error: no 'void LabMetaData::SetData()' member function declared in class 'LabMetaData'
  prog.cpp:44:28: error: no 'void LabMetaData::ShowData()' member function declared in class 'LabMetaData'
  prog.cpp: In function 'int main()':
  prog.cpp:58:17: error: no matching function for call to 'LabMetaData::LabMetaData()'
  prog.cpp:21:1: note: candidates are: LabMetaData::LabMetaData(int, std::string, std::string, int, int, int, std::string)
  prog.cpp:5:1: note:                 LabMetaData::LabMetaData(const LabMetaData&amp;)
  prog.cpp:61:10: error: 'class LabMetaData' has no member named 'ShowData'
  prog.cpp:63:10: error: 'class LabMetaData' has no member named 'SetData'
  prog.cpp:66:10: error: 'class LabMetaData' has no member named 'ShowData'
  prog.cpp:68:9: error: 'Lab4' was not declared in this scope
  prog.cpp:72:10: error: 'class LabMetaData' has no member named 'ShowData'
  </code></pre>