VB.Net - Exporting to Excel Variable Number of Columns

Good Day Experts!

Usually, when I build a report from SQL to Excel in VB.Net, I know the column names and I set them in the code.  

Now, I have a situation where I need to "Select *..." from a table with over 30 columns.  
Aside from setting up an array of Excel column names(A,B,C...AA,AB,AC and so on), is there a way to programataically start with value "A" and keep "retrieving" the next value without getting it from a pre-populated array?

Thanks,
jimbo99999
Jimbo99999Asked:
Who is Participating?
 
CodeCruiserCommented:
With my approach

For i As Integer = 0 to dTable.Rows.Count
   for j As Integer = 0 to dTable.Columns.Count

You can can the columnname using a function supplied at below link. Just pass it j

So this

With oSheet.Range("A" + CStr(ExcelRow))

will become

With oSheet.Range(ColumnName(j) + CStr(ExcelRow))


http://stackoverflow.com/questions/297213/translate-a-column-index-into-an-excel-column-name
0
 
CodeCruiserCommented:
I assume you are exporting from datatable to excel? You can use an inner loop

For i As Integer = 0 to dTable.Rows.Count
   for j As Integer = 0 to dTable.Columns.Count
0
 
Ioannis ParaskevopoulosCommented:
Hi,

You could retrieve the column names by running the following:

SELECT	sc.name
FROM	sysobjects so
		JOIN syscolumns sc
			ON sc.id = so.id
WHERE   so.name = @TableName
ORDER BY colorder

Open in new window


Just provide the tablename as you would for the select * from ....

Giannis
0
Cloud Class® Course: Microsoft Exchange Server

The MCTS: Microsoft Exchange Server 2010 certification validates your skills in supporting the maintenance and administration of the Exchange servers in an enterprise environment. Learn everything you need to know with this course.

 
Jimbo99999Author Commented:
Good Day, I apologize...I did not articulate my question very good.  Let me try again.

Usually, when I build a report from SQL to Excel in VB.Net, I know the column names and I set them in the code.  Since I know the column names, I set-up my column formatting ahead of time with the following code:

With oSheet.Range("A" + CStr(ExcelRow))
        .Font.Size = 12
        .Font.Name = "Segoe UI"
        .Font.Underline = True
        .Value = "Pro Number"
        .HorizontalAlignment = Excel.XlVAlign.xlVAlignCenter
End With

Now, I want to execute a Select * statement where I won't know ahead of time the amount of columns or the columns names ahead of time to do my above column cormatting.  When I loop through my DataTable after executing the Select * statment, how can I get that Excel column letter reference to use in the above code?

So, each time through the loop I would get the next letter A through Z.  Then I have to keep track of when I get to Z since the next references are AA through AZ.  

I guess the deliverable I need help with is getting the next letter in the alphabet each time through the loop.

Thanks,
jimbo99999
0
 
Ioannis ParaskevopoulosCommented:
Hi,

You have a datatable loaded, right?
As CodeCruiser said you may do:
for i As Integer = 0 to dTable.Columns.Count
    With oSheet.Range(Chr(i+65) + CStr(ExcelRow))
        .Font.Size = 12
        .Font.Name = "Segoe UI"
        .Font.Underline = True
        .Value = "Pro Number"
        .HorizontalAlignment = Excel.XlVAlign.xlVAlignCenter
    End With
next

Open in new window


It isn't really pretty but i would do the job. if .value is the column name then you may do the following:

for i As Integer = 0 to dTable.Columns.Count
    With oSheet.Range(Chr(i+65) + CStr(ExcelRow))
        .Font.Size = 12
        .Font.Name = "Segoe UI"
        .Font.Underline = True
        .Value = dTable.Columns(i).ColumnName
        .HorizontalAlignment = Excel.XlVAlign.xlVAlignCenter
    End With
next

Open in new window


Giannis
0
 
Jimbo99999Author Commented:
Ok, I see.  So I will be referencing the Excel column by the column name from the table.
0
 
ElrondCTCommented:
I use the following function to get a column letter name from a number:
    Public Function ExcelColumnName(ByVal intCol As Integer) As String
        ' Convert an integer to the Excel column name: 1=A, 26=Z, 27=AA, etc.
        If intCol <= 26 Then
            Return CStr(Chr(intCol + 64))
        Else
            Dim intPrefix As Integer = (intCol - 1) \ 26
            intCol = ((intCol - 1) Mod 26) + 1          ' Force range 1-26, not 0-25
            Return CStr(Chr(intPrefix + 64)) & CStr(Chr(intCol + 64))
        End If
    End Function

Open in new window

You can then loop through numbers for the columns.
0
 
ElrondCTCommented:
Sorry, CodeCruiser, I didn't notice before posting that you linked to a similar answer.
0
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

All Courses

From novice to tech pro — start learning today.