4c – Logical Operations Lingma Acheson Department of Computer and Information Science, IUPUI CSCI N331 VB.NET Programming

Logical Operators AndAlso –Connects two or more conditions –All the conditions have to be true for the compound condition to be true –E.g. ‘Grade will be A if both conditions are satisfied If intFinalScore >= 85 AndAlso strExtra = “Pass” Then strLetterGrade = “A” End If ‘The loan amount will be if the person is a student And income is lower ‘than ‘Otherwise (either a student or low income), the amount will be If strIdentity = “student” AndAlso intIncome < 10000Then intLoanAmount = Else intLoanAmount = End If 2

Logical Operators OrElse –Connects two or more conditions –At least one condition has to be true for the compound condition to be true (also true if more than one condition is true). –E.g. ‘Grade will be A if it meets at least one of the conditions. ‘The grade will be A if either the final score is 90+ or the project score is 95+ ‘The score will still be A if both conditions are met. If intFinalScore >= 90 OrElse intProject >= 95 Then strLetterGrade = “A” End If 3

Logical Operators Xor –Connects two or more conditions –Exclusive OR: Only one condition can be true for the compound condition to be true. –E.g. ‘Grade will be D only if it meets one of the conditions. ‘The grade will be D if either the final score is <60 or the project score is < 60 ‘If both are < 60, the grade will be F. If intFinalScore < 60 Xor intProject < 60 Then strLetterGrade = “D” Else strLetterGrade = “F” End If 4

Logical Operators Xor ‘An example determining discount ‘Either a senior citizen or a VIP member can get 10% discount If strStatus = “senior” Xor strMember = “VIP” Then intDiscount = 10 ‘The above If condition will be false if the person is a senior VIP or neither, thus ‘it will false into the below ElseIf branch ElseIf strMember = “VIP” Then ‘If a senior VIP, will get 20% discount intDiscount = 20 End If 5

Logical Operators Not –Negate the condition. If the condition evaluates to true, negate the condition will make it false, and vise versa. E.g. If Not strStatus = “kids” Then ‘ if status is not kids, get 10% intDiscount = 10 ‘ discount Else ‘ If status is kids, get 20% discount intDiscount = 20 End If 6