Question

1. Please use a single example that uses the If ---Then---Else statement to code single-alternative and dual-alternative selection structures.

2. SELECT CASE (include case else statement) vs. IF....ELSE..block, give an example of how to use each structure

Please keep it as simple as possible!

Answer 1

1.

a. Single alternative Example

if (power is on) Then

Switch on the Light;

b. Dual alternative Example

If--- Then---Else statement is used, based on only if there is only two possible case.

Example : If (age >= 18) Then You can vote;

Else You can't vote.

2. SELECT CASE is used based on given character or Integeral value only.

Example: Consider integer input as day number. Then, we can write SELECT CASE as day as shown  below:

Dim number As Integer = 4

Select Case number

Case 1 to 7 PRINT "Weekday"

Case ELSE PRINT "Invalid Input"

End Select

For this: output would be Weekday

Use of if-Else and Select Case:

I. If input type is always same then use select case.

II. If condition is very different and not fixed by the value, use if-else