C#

int x = 25;
Color c = GetColor (x);


public Color GetColor
  (int x)
{
  if ((x <= 5) && (x >= -5))
     return Color.Blue;
  if ((x <= 15) && (x >= -15))
     return Color.Yellow;
  if ((x <= 25) && (x >= -25))
     return Color.Green;
  return Color.Red;
}

Member 11956589 wrote:

which is filled from a SQL database using a SELECT query

foreach (DataRow animalsDataRow in ds.Tables["Animals"].Rows)
         {
            // Do Something with animalsDataRow<br />
         }

Member 11956589 wrote:

and tells me that there is a Null value.

DataSet ds = new Dataset();

private void searchBtn_Click(object sender, EventArgs e)
    {


  string connectionString = "Data Source= ... your connection string";

            SqlDataAdapter da = new SqlDataAdapter(
                "SELECT your fields " +
                "FROM Animals" +
                "WHERE gender = @searchFor",
            connectionString);

            da.SelectCommand.Parameters.AddWithValue("@searchFor", tbSearch.Text);
            // Fill the DataSet.
            da.Fill(ds);

            DataTable animals = ds.Tables["Animals"];
            foreach (DataRow row in animals.Rows)
            {
               //operation with rows
            }
        }

namespace YourNameSpace
{
    public abstract class Animal
    {
        public string Name;

        public abstract string MyAbstractMethod();

        public virtual string MyVirtualMethod()
        {
            return string.Format("Animal: {0}", Name);
        }
    }

    public class Mammal : Animal
    {
        public override string MyAbstractMethod()
        {
            return string.Format("Mammal: {0}", Name);
        }

        public new string MyVirtualMethod()
        {
            return string.Format("Mammal: {0}", Name);
        }
    }

    public class Dog : Mammal
    {
        public new string MyAbstractMethod()
        {
            return string.Format("Dog: {0}", Name);
        }

        public new string MyVirtualMethod()
        {
            return string.Format("Dog: {0}", Name);
        }
    }
}

namespace YourNameSpace
{
    private void TestAnimal()
    {
        Dog myDog = new Dog();
        myDog.Name = "Spot";
    
        string dname = myDog.MyAbstractMethod();
    
        string mname = (myDog as Mammal).MyAbstractMethod();
    
        string aname = (myDog as Animal).MyAbstractMethod();
    
        string dname2 = myDog.MyVirtualMethod();
    
        string mname2 = (myDog as Mammal).MyVirtualMethod();
    
        string aname2 = (myDog as Animal).MyVirtualMethod();

        // set a break-point here and observe variable values:
        // repeat until 'understanding' happens :)
    }
}