DO LOOP
————–
Do loop has 2 version. one where condition is evaluated at the beginning
whose Syntax:
Do [while | until] [condition]
[statements]
[exit do]
[increment | statements]
Loop
or one where condition is evaluated at the end.
whose syntax
Do
[statements]
[exit do]
[increment | statements]
Loop [while | until] [condition]
For example checking end of file using EOF() function
Do until EOF(1)
line input #1, Data$
Form1.tb.text = Form1.tb.text + Data$
Loop
FOR LOOP
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Do loop doesnot require loop index but for loop does. So used when number of iteration is known.
SYNTAX
For index = start to end increment [1 | -1]
[statements]
[Exit for]
[statements]
Next index
for example
Dim intindex, total
total = 0
For intindex = 1 to 10
total = total + 1
next intindex
Default incrementation is +1.
FOR EACH LOOP
Use is to loop over elements in an Array or Collection
For each element in group
[statements]
[exit for]
[statements]
next element
For example
Dim IArray(1 to 3)
IArray(1) = 1
IArray(2) = 2
IArray(3) = 3
For each Arrayitem in IArray
msgbox (Str(Arrayitem))
next Arrayitem
WHILE LOOP
used when we want to stop loop when condition is no longer true.
SYNTAX
while condition
[statements]
Wend
for example
Dim intinput
intinput =-1
While intinput<0
intinput = InputBox(“Enter positive number”)
Wend
