Unit 8: Control Statements

Excel Macros Level 1

Control Functions

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Control Structures

All applications can be written in terms of: Sequence Structures Selection Structures (or Selection Statements) Repetition Structures (or Repetition Statements)

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Flowchart Legend

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Sequence Structures

Typically built into languageAllows statements to be

executed one after another

Add x and y together.Display the result.

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Selection Structures

Allows code to be executed based on conditions

If the number is even display it

Otherwise, do not display it

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Repetition Structures

Allows code to be repeated as necessary

While the number is less than or equal to 100, display it.

Once it is over 100, end the program

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The If…Then Statement

Selection Statement:

If condition Then' statements go here

ElseIf condition2 Then' more statements

Else' more statements

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The For Loop

Repetition Statement:

For counter = start To end' statements go here

Next counter

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The For Loop

By default a For loop: Sets counter to the value start Executes the code within the loop body Increments counter Continues looping until counter exceeds the end

value

Can use Exit For to leave For loop early

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The For Loop

Can change the step size:For i = 1 To 10 Step 2

' code block goes hereNext i

Can change the direction:For i = 1 To 10 Step -5

' code block goes hereNext i

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The For Each Loop

Repetition Statement:

For Each objectVar In collection' code block goes here

Next objectVar

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The For Each Loop

Loops through a collection of objectsEach iteration places the next object in the

variable objectVar

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The Do Loop

Repetition Statement:

Do While condition' code block goes here

Loop

Repeats the code block while condition is true

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The Do Loop

Repetition Statement:

Do' code block goes here

Loop While condition

Repeats the code block while condition is trueWill execute at least once (as condition is checked last)

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The Do Loop

Repetition Statement:

Do Until condition' code block goes here

Loop

Repeats the code block until condition becomes true

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The Select Case Statement

Selection Statement:

Select Case testVarCase value1

' code to execute if testVar = value1Case value2

' code to execute if testVar = value2Case Else

' statements to execute otherwiseEnd Select

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