Defining an expression-bodied member

In the next stage, we will begin by defining an expression member, so enter the following between a set of curly braces:

double FromStringToDouble(string s) => Convert.ToDouble(s);

This line shows a new way of creating functions. That's what this is essentially. Instead of putting curly braces within the line, you can now just put something such as a Lambda expression, => in this case. Then the thing to be converted to a double data type will be the s string. It's also more streamlined; it looks a little more modern, like an expression-bodied member, like a function. Remember that functions are members of classes.

So, in the next stage, we'll define the Button click event below this line. If you go back to the Design view and double-click the button, it'll stick in the following line automatically:

protected void Button1_Click(object sender, EventArgs e)

Next, enter the following between a set of curly braces beneath the preceding line:

string[] vals = TextBox1.Text.Split(new char[] { ',' });