Question

    A   B   C
A1  1   2   3
B1  4   5   6
C1  7   8   9

Using the above (like table) going to get the value for the given header value.
ex: if(column=” A” && row = “B1″) then value=”4”

without using a often if loops,Is there any idea to fetch the values using C#.

Note: The above is not a table or structure getting form DB or any memory objects .It is just a value mapping for the given headervalues.

Answer 1

The simplest solution would probably be to use a Dictionary<Tuple<string, string>, int>, assuming you’re using .NET 4. It would work something like this:

private readonly Dictionary<Tuple<string, string>, int> Table = 
    new Dictionary<Tuple<string, string>, int>
{
    { Tuple.Create("A1", "A"), 1 },
    { Tuple.Create("A1", "B"), 2 },
    { Tuple.Create("A1", "C"), 3 },
    { Tuple.Create("B1", "A"), 4 },
    { Tuple.Create("B1", "B"), 5 },
    { Tuple.Create("B1", "C"), 6 },
    { Tuple.Create("C1", "A"), 7 },
    { Tuple.Create("C1", "B"), 8 },
    { Tuple.Create("C1", "C"), 9 },
};

public int this[string row, string column]
{
    get
    {
        return Table[Tuple.Create(row, column)];
    }
}

If you’re not using .NET 4 you could fake it by combining the row and column together, e.g. by concatenating them and adding a slash: “A/A1”, “B/B1” etc, and then having a Dictionary<string, int>. It’s pretty ugly though – I’d be tempted to write my own RowColumn structure to avoid that.

Another alternative would be to keep two dictionaries, each mapping row names or column names to indexes, and then an int[,] array for the values. This has the benefit that you can identify when a row or column is invalid. If you really only have a few rows or columns, a simple list of strings would probably be just as fast or faster:

private readonly List<string> RowNames = new List<string> { "A1", "B1", "C1" };
private readonly List<string> ColumnNames = new List<string> { "A", "B", "C" };
private readonly int[,] Values = { { 1, 2, 3 }, { 4, 5, 6 }, { 7, 8, 9 } };

public int this[string row, string column]
{
    get
    {
        int rowIndex = RowNames.IndexOf(row);
        if (rowIndex == -1)
        {
            throw new ArgumentOutOfRangeException("Invalid row specified");
        }
        int columnIndex = ColumnNames.IndexOf(column);
        if (columnIndex == -1)
        {
            throw new ArgumentOutOfRangeException("Invalid column specified");
        }
        return Values[rowIndex, columnIndex];
    }
}