Learn VBA : Sort an Array

by

I quite often, to get ideas for articles look at the things people search for on the site. And recently I did just that and noted that someone looked up how to do a VBA array sort. If that was you , then this quick article is for you.

First off lets define the array and populate it.

Dim oArray[10]
     
    oArray[0] = "J"
    oArray[1] = "I"
    oArray[2] = "H"
    oArray[3] = "D"
    oArray[4] = "F"
    oArray[5] = "G"
    oArray[6] = "E"
    oArray[7] = "B"
    oArray[8] = "C"
    oArray[9] = "A"

In this example we are going to do a bubble sort, but there are lots of different types. Bubble is by far the easiest at the cost of speed, it is by no means the fastest sort.

    
   
Dim iFirst,iLast,iCount,iNestCount
Dim sTemp,sList
     
    iFirst = LBound(oArray) 
    iLast = UBound(oArray) 
    For iCount = iFirst To iLast - 1 
        For iNestCount = iCount + 1 To iLast 
            If oArray[iCount] > oArray[iNestCount] Then 
                sTemp = oArray[iNestCount] 
                oArray[iNestCount] = oArray[iCount]
                oArray[iCount] = sTemp 
            End If 
        Next
    Next

So what does our code do, well we first of we find the first record in our array and then we find the last , and then we begin to loop our array. Next we start to loop the array again , starting with the element we are on and checking to see if any of the following elements are greater than the one we currently have selected in the first loop , if it is greater then we swap them around and then continue on , so to help you visualise this, this is what happens

iCount = 0,  Array[iCount] = J / iNestCount = 1,  Array[iNestCount] = I
SWAP,  Array[iCount] = I / Array[iNestCount] = J
iCount = 0,  Array[iCount] = I / iNestCount = 2,  Array[iNestCount] = H
SWAP,  Array[iCount] = H / Array[iNestCount] = I
iCount = 0,  Array[iCount] = H / iNestCount = 3,  Array[iNestCount] = D
SWAP,  Array[iCount] = D / Array[iNestCount] = H
iCount = 0,  Array[iCount] = D / iNestCount = 4,  Array[iNestCount] = F
iCount = 0,  Array[iCount] = D / iNestCount = 5,  Array[iNestCount] = G
iCount = 0,  Array[iCount] = D / iNestCount = 6,  Array[iNestCount] = E
iCount = 0,  Array[iCount] = D / iNestCount = 7,  Array[iNestCount] = B
SWAP,  Array[iCount] = B / Array[iNestCount] = D
iCount = 0,  Array[iCount] = B / iNestCount = 8,  Array[iNestCount] = C
iCount = 0,  Array[iCount] = B / iNestCount = 9,  Array[iNestCount] = A

and this keeps on going until we have looped round all the items in the array. Are final bit of code just lets us display the results.

     
    For iCount = 1 To UBound(oArray) 
        sList = sList + oArray[iCount] 
    Next 
    
    Debug.MsgBox(sList)

So there you have it some code to sort an array. I hope you find it useful. Please don’t forget if you cannot find what you want , leave a comment on the “ASK US post” and I will respond to you with an answer if I can.

Leave a Comment