Refactoring if statements with radiobuttons.checked

Question

There are two radio buttons which give different prices. Example: elektric2 is selected and 3 days rent. Electric bike = 200 euro + 30 euro per day (200 eu + (30*3)).

How can I refactor this because I have 60+ lines of code for all the options.

Here is a bit of the entire code:

if (radioButtonElectric2.Checked && radioButtonADay.Checked)
{
    electric2 = electric2 + 1 * 30;
    labelSubTotal.Text = "Subtotal:€" + electric2.ToString();
}
else if (radioButtonElectric2.Checked && radioButtonThreeDays.Checked)
{
    electric2 = electric2 + 3 * 30;
    labelSubTotal.Text = "Subtotal:€" + electric2.ToString();
}
else if (radioButtonElectric2.Checked && radioButtonSevenDays.Checked)
{
    electric2 = electric2 + 7 * 30;
    labelSubTotal.Text = "Subtotal:€" + electric2.ToString();
}
else if (radioButtonElectrical2.Checked && radioButtonFourteenDays.Checked)
{
    electric2 = electric2 + 14 * 30;
    labelSubTotal.Text = "Subtotal:€" + electric2.ToString();
}

Answer 1

Your equation basically boils down to three amounts.

1. Base Price
2. Renting Days
3. Daily Rate

Splitting these three things into individual functions makes your code much simpler.

public decimal GetBasePrice()
{
    return 
        radioButtonElectric1.Checked ? 60 :
        radioButtonElectric2.Checked ? 80 :
        radioButtonGas1.Checked ? 55 :
        0;
}
public int GetRentingDays()
{
    return
        radioButtonADay.Checked ? 1 :
        radioButtonThreeDays.Checked ? 3 :
        radioButtonSevenDays.Checked ? 7 :
        radioButtonFourteenDays.Checked ? 14 :
        0;
}
public decimal GetDailyRate()
{
    return 
        radioButtonElectric1.Checked ? 20 :
        radioButtonElectric2.Checked ? 30 :
        radioButtonGas1.Checked ? 25 :
        0;
}

In the end the final code is much simpler:

decimal subTotal = GetBasePrice() + GetRentingDays() * GetDailyRate();