1. Welcome back to Software Development!

2. Loops

3. Loops
3 types of loops:

4. Loops
3 types of loops:
while

5. Loops 3 types of loops: while
used when you don’t know how many times to loop

6. Loops 3 types of loops: while for
used when you don’t know how many times to loop
for

7. Loops 3 types of loops: while for
used when you don’t know how many times to loop
for
used when you do know how many times to loop

8. Loops 3 types of loops: while for foreach
used when you don’t know how many times to loop
for
used when you do know how many times to loop
foreach

9. Loops 3 types of loops: while for foreach
used when you don’t know how many times to loop
for
used when you do know how many times to loop
foreach
used to work on parts of a group, one at a time

10. All Loops…

11. All Loops…
Use a loop control variable

12. All Loops… Use a loop control variable
First: Initialize the loop control variable

13. All Loops… Use a loop control variable
First: Initialize the loop control variable
If you don’t, you likely won’t be able to even get into the loop

14. All Loops… Use a loop control variable
First: Initialize the loop control variable
If you don’t, you likely won’t be able to even get into the loop
Next: Check the loop control variable to see if keep looping

15. All Loops… Use a loop control variable
First: Initialize the loop control variable
If you don’t, you likely won’t be able to even get into the loop
Next: Check the loop control variable to see if keep looping
Finally: Change (often increment) the loop control variable

16. All Loops… Use a loop control variable
First: Initialize the loop control variable
If you don’t, you likely won’t be able to even get into the loop
Next: Check the loop control variable to see if keep looping
Finally: Change (often increment) the loop control variable
If you don’t, you won’t be able to exit the loop…infinite loop

17. While Loop

18. While Loop
Used when you don’t know how many times you need to loop

19. While Loop Used when you don’t know how many times you need to loop
Init the loop control variable outside and before the loop

20. While Loop Used when you don’t know how many times you need to loop
Init the loop control variable outside and before the loop
Check the loop control variable in the while statement condition

21. While Loop Used when you don’t know how many times you need to loop
Init the loop control variable outside and before the loop
Check the loop control variable in the while statement condition
Change the loop control variable in the body of the while loop

22. While Loop Used when you don’t know how many times you need to loop
Init the loop control variable outside and before the loop
Check the loop control variable in the while statement condition
Change the loop control variable in the body of the while loop
Often increment the loop control variable when simply counting

23. While Loop while ( check loop control variable)
Used when you don’t know how many times you need to loop
Init the loop control variable outside and before the loop
Check the loop control variable in the while statement condition
Change the loop control variable in the body of the while loop
Often increment the loop control variable when simply counting
while ( check loop control variable)

24. While Loop Example
ArrayList myList = new ArrayList(); // create the list
myList.Add(4); // fill the list
int position; // create loop control variable
position = 0; // init loop control variable
while (position < myList.Count ) // loop until thru the list {
Console.WriteLine(“Next #: ”, myList[position]);
position++; // increment counter }

25. Task Write a program using a while loop to print the first 5 integers
Name the project “loops”
Display each number on its own line with “Next #:
Before the loop, display the message “While loop”

26. For Loop

27. For Loop
Used when you *do* know how many times you need to loop

28. For Loop
Used when you *do* know how many times you need to loop
for (

29. For Loop for ( init the loop control variable ;
Used when you *do* know how many times you need to loop
for ( init the loop control variable ;

30. For Loop for ( init ; check the loop control variable ;
Used when you *do* know how many times you need to loop
for ( init ; check the loop control variable ;

31. For Loop for ( init ; check ; change the loop control variable)
Used when you *do* know how many times you need to loop
for ( init ; check ; change the loop control variable)

32. For Loop for ( init ; check ; change )
Used when you *do* know how many times you need to loop
for ( init ; check ; change )

33. For Loop

34. For Loop ArrayList myList = new ArrayList(); // create list
myList.Add(4); // fill the list
int position; // create loop control variable
// Loop until thru the list printing each number
for ( position= 0 ; position < myList.Count ; position++ {
Console.WriteLine(“Looped” + counter + “ times.”); }
Init loop control variable
Check loop control variable
Increment loop control variable

35. For Loop ArrayList myList = new ArrayList(); // create list
myList.Add(4); // fill the list

36. For Loop ArrayList myList = new ArrayList(); // create list
myList.Add(4); // fill the list
int position; // create loop control variable

37. For Loop ArrayList myList = new ArrayList(); // create list
myList.Add(4); // fill the list
int position; // create loop control variable
// Loop until thru the list printing each number

38. For Loop ArrayList myList = new ArrayList(); // create list
myList.Add(4); // fill the list
int position; // create loop control variable
// Loop until thru the list printing each number
for ( {
Console.WriteLine(“Looped” + counter + “ times.”); }

39. For Loop ArrayList myList = new ArrayList(); // create list
myList.Add(4); // fill the list
int position; // create loop control variable
// Loop until thru the list printing each number
for ( position= 0 ; {
Console.WriteLine(“Looped” + counter + “ times.”); }

40. For Loop ArrayList myList = new ArrayList(); // create list
myList.Add(4); // fill the list
int position; // create loop control variable
// Loop until thru the list printing each number
for ( position= 0 ; {
Console.WriteLine(“Looped” + counter + “ times.”); }
Init loop control variable

41. For Loop ArrayList myList = new ArrayList(); // create list
myList.Add(4); // fill the list
int position; // create loop control variable
// Loop until thru the list printing each number
for ( position= 0 ; position < myList.Count ; {
Console.WriteLine(“Looped” + counter + “ times.”); }
Init loop control variable

42. For Loop ArrayList myList = new ArrayList(); // create list
myList.Add(4); // fill the list
int position; // create loop control variable
// Loop until thru the list printing each number
for ( position= 0 ; position < myList.Count ; {
Console.WriteLine(“Looped” + counter + “ times.”); }
Init loop control variable
Check loop control variable

43. For Loop ArrayList myList = new ArrayList(); // create list
myList.Add(4); // fill the list
int position; // create loop control variable
// Loop until thru the list printing each number
for ( position= 0 ; position < myList.Count ; position++ ) {
Console.WriteLine(“Looped” + counter + “ times.”); }
Init loop control variable
Check loop control variable

44. For Loop ArrayList myList = new ArrayList(); // create list
myList.Add(4); // fill the list
int position; // create loop control variable
// Loop until thru the list printing each number
for ( position= 0 ; position < myList.Count ; position++ ) {
Console.WriteLine(“Looped” + counter + “ times.”); }
Init loop control variable
Check loop control variable
Increment loop control variable

45. For Loop ArrayList myList = new ArrayList(); // create list
myList.Add(4); // fill the list
int position; // create loop control variable
// Loop until thru the list printing each number
for ( position= 0 ; position < myList.Count ; position++ ) {
Console.WriteLine(“Looped” + counter + “ times.”); }

46. Task Add to your “loops” program: After your while loop…
Add a for loop to print the first 5 integers
Display each number on its own line with “Next #:
Before the loop, display the message “For loop”

47. Foreach Loop

48. Foreach Loop
Used to work on parts of a group, one at a time

49. Foreach Loop Used to work on parts of a group, one at a time
The loop control variable is created in the foreach statement

50. Foreach Loop Used to work on parts of a group, one at a time
The loop control variable is created in the foreach statement
The foreach automatically checks and changes the loop control variable

51. Foreach Loop foreach ( Used to work on parts of a group, one at a time
The loop control variable is created in the foreach statement
The foreach automatically checks and changes the loop control variable
foreach (

52. Foreach Loop foreach ( create loop control variable
Used to work on parts of a group, one at a time
The loop control variable is created in the foreach statement
The foreach automatically checks and changes the loop control variable
foreach ( create loop control variable

53. Foreach Loop foreach ( create loop control variable in
Used to work on parts of a group, one at a time
The loop control variable is created in the foreach statement
The foreach automatically checks and changes the loop control variable
foreach ( create loop control variable in

54. Foreach Loop
Used to work on parts of a group, one at a time
The loop control variable is created in the foreach statement
The foreach automatically checks and changes the loop control variable
foreach ( create loop control variable in group to work with )

55. Foreach Example

56. Foreach Example
ArrayList myList = new ArrayList(); // create list

57. Foreach Example ArrayList myList = new ArrayList(); // create list
myList.Add(4); // fill the list

58. Foreach Example ArrayList myList = new ArrayList(); // create list
myList.Add(4); // fill the list
// Loop through the list item by item

59. Foreach Example ArrayList myList = new ArrayList(); // create list
myList.Add(4); // fill the list
// Loop through the list item by item
foreach ( ) { … }

60. Foreach Example ArrayList myList = new ArrayList(); // create list
myList.Add(4); // fill the list
// Loop through the list item by item
foreach ( int numFmList { … }

61. Foreach Example ArrayList myList = new ArrayList(); // create list
myList.Add(4); // fill the list
// Loop through the list item by item
foreach ( int numFmList { … }
Create loop control variable

62. Foreach Example ArrayList myList = new ArrayList(); // create list
myList.Add(4); // fill the list
// Loop through the list item by item
foreach ( int numFmList in { … }
Create loop control variable

63. Foreach Example ArrayList myList = new ArrayList(); // create list
myList.Add(4); // fill the list
// Loop through the list item by item
foreach ( int numFmList in myList) { … }
Create loop control variable

64. Foreach Example ArrayList myList = new ArrayList(); // create list
myList.Add(4); // fill the list
// Loop through the list item by item
foreach ( int numFmList in myList) { … }
Create loop control variable
Automagically check & change loop control variable

65. Foreach Example ArrayList myList = new ArrayList(); // create list
myList.Add(4); // fill the list
// Loop through the list item by item
foreach ( int numFmList in myList) {
if ( numFmList == matchNum ) … }

66. Task Add to your “loops” program: After your for loop…
Create an ArrayList and fill it with the first 5 integers
Use a foreach loop to print the first 5 integers from the ArrayList
Display each number on its own line with “Next #:
Before the loop, display the message “Foreach loop”

67. Clear and Unclear Windows