FlashCard101

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Introduction

I was taking a Conversational Spanish course last year and a Microsoft course that required a lot of memorization and decided that the best way to learn a little more about C# was to create a Flash card program. The problem with most flash card programs are that you are stuck with their dictionaries and you can not adjust the pace.

Background

The first thing was how would I store the data so that the maximum number of people could use the program with the least amount of software (aka: Access and SQL Server) so I decided to build the data schema in code and then save and open the DataSets as xml files.

This program demonstrates several useful techniques in using the System.Data namespace as well as the slider control and Timer.

Using the code

There are three forms frmAbout contains the version info and copyright notice, frmEditDict which is used to edit the dictionaries, and frmFlash which is the main form and displays the words and definitions.

To create the DataSet for the dictionary I used the following code.

static void initDS()
    {
      //create our schema/table 

      ds=new DataSet("DataSet");
      DataTable dt=ds.Tables.Add("Dictionary");

      DataColumn dc=dt.Columns.Add("ID",typeof(Int32));
      dc.AutoIncrement=true;
      dc.AllowDBNull=false;
      dc.AutoIncrementStep=1;

      //create the primary key

      DataColumn[] keys=new DataColumn[1];
      keys[0]=dc;
      dt.PrimaryKey=keys;
      
      dc=dt.Columns.Add("Word",typeof( String));
      dc.AllowDBNull=false;
      
      dc=dt.Columns.Add("Def",typeof( String));
      dc.AllowDBNull=false;
      
    }

Each time the tick event of the Timer is fired we check a boolean value bDisplayWord if it is true then we select another random word from the dictionary and display it. Then we toggle the bDisplayWord to false and display the definition the next time the Timer is fired.

private void timer1_Tick(object sender, System.EventArgs e)
    {
      
      if(bDisplayWord)
      {// display word

        DataTable dt=ds.Tables[0];
        System.Random rnd=new System.Random();
        currentIndex=(Int32) (rnd.NextDouble()*dt.Rows.Count);
        txtWord.Text=currentIndex.ToString();
        DataRow dr;
        dr=dt.Rows[currentIndex];
        txtWord.Text=dr.ItemArray[1].ToString();
        txtDefinition.Text="";
      }
      else
      {//else display Definition

        txtDefinition.Text = 
           ds.Tables[0].Rows[currentIndex].ItemArray[2].ToString();
      }

      //switch display component

      bDisplayWord = !bDisplayWord;
      
    }

To save and load the DataSet I simply use the save and open dialogs combined with the ReadXml and WriteXml Methods of the System.Data.DataSet class.

Points of Interest

This code was one of my first functional utilities written with C#. It demonstrates several objects of the .NET framework: DataSet, grids, sliders, xml files, Timers, and forms.