” hide a gridview column if all the row values for that column are null”

Here is a code snippet I posted  before:

Here is working sample from a previous thread:

1.Add these two events to the gridview

OnRowCreated=”GridView1_OnRowCreated” 
OnDataBound=”GridView1_DataBound”   

2.In the code behind:

C#:

Boolean[] notNulls;
 
    protected void Page_Load(object sender, EventArgs e)
    {
      int colCount = GridView1.Columns.Count;
        notNulls = new Boolean[colCount];
       
        for (int i = 0; i < colCount; i++)
        {
            notNulls[i]=false;
        }
    }
    protected void GridView1_DataBound(object sender, EventArgs e)
    {
        for (int cellNum = GridView1.Columns.Count – 1; cellNum >= 0; cellNum–)
        {
            for (int i = 0; i < notNulls.Length; i++)
            {
                Boolean myLocalBool = notNulls[i];
                if (myLocalBool == false)
                {               
                    GridView1.Columns[i].Visible = false;
                   
                }
            }

        } 
    }

    protected void GridView1_OnRowCreated(object sender, GridViewRowEventArgs e)
    {
       
        if (e.Row.RowType == DataControlRowType.DataRow)
        {

            DataRowView drv = (DataRowView)e.Row.DataItem;

            for (int i = 0; i < GridView1.Columns.Count; i++)
            {
                if (!(drv[i] == DBNull.Value))
                {
                    notNulls[i] = true;
                   
                }
              
            }

        }          

    }

VB.NET:

Dim notNulls As Boolean()

    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        Dim colCount As Integer = GridView1.Columns.Count
        notNulls = New Boolean(colCount) {}

        Dim i As Integer = 0
        While i < colCount
            notNulls(i) = False
            i = i + 1
        End While

    End Sub
    Protected Sub GridView1_DataBound(ByVal sender As Object, ByVal e As EventArgs)
        Dim cellNum As Integer = GridView1.Columns.Count – 1
        While cellNum > 0
            Dim i As Integer = 0

            While i < GridView1.Columns.Count ‘Changed from notNulls.Length in C#

                Dim myLocalBool As Boolean = notNulls(i)
                If myLocalBool = False Then
                    GridView1.Columns(i).Visible = False

                End If
                i = i + 1

            End While
            cellNum = cellNum – 1

        End While
    End Sub
    Protected Sub GridView1_OnRowCreated(ByVal sender As Object, ByVal e As GridViewRowEventArgs)

        If e.Row.RowType = DataControlRowType.DataRow Then
            Dim drv As DataRowView = CType(e.Row.DataItem, DataRowView)
            Dim i As Integer = 0

            While i < GridView1.Columns.Count

                If Not drv(i) Is DBNull.Value Then

                    notNulls(i) = True

                End If

                i = i + 1
              
            End While
        End If
    End Sub

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List file info into a database table

Here is a handly script from Jeff Moden:
http://www.sqlservercentral.com/Forums/Topic540627-338-1.aspx
You can modify the code to save all infor to a permenent table:
 
Here is code Jeff posted: (Only change it to save the data to a permenent table instead of a temp one)
 

ALTER PROCEDURE [dbo].[GetDirDetails_Jeff_Moden]

http://www.sqlservercentral.com/Forums/Topic540627-338-1.aspx

/**************************************************************************************************

Purpose:

Replacement code for the sp_GetFileDetails proc that was available in SQL Server 2000

which is no longer available in SQL Server 2005 except this gets all the file details

for all the files in the directory provided.

Notes:

1. If the directory does not exist or there are no files in the directory, an empty

result set will be returned.

2. If the trailing backslash on the path is missing, it will be added automatically.

3. No error checking is done. Either a valid result set is returned or an empty

result set is returned (much like a function operates).

Usage:

EXEC dbo.GetDirDetails ‘drive:path or UNC’

Revision History:

Rev 00 – 05/23/2008 – Jeff Moden

– Initial concept borrowed from Simple-Talk.com (Phil Factor) and

modified for multiple files.

Rev 01 – 05/25/2008 – Jeff Moden

– Formalize the code for use.

**************************************************************************************************/

–===== Declare the I/O parameters

@piFullPath

VARCHAR(128)

AS

–===== Suppress the auto-display of rowcounts so as not to interfere with the returned

— result set

SET NOCOUNT ON

–=================================================================================================

— Local variables

–=================================================================================================

–===== These are processing control and reporting variables

DECLARE

@Counter INT –General purpose counter

DECLARE

@CurrentName VARCHAR(256) –Name of file currently being worked

DECLARE

@DirTreeCount INT –Remembers number of rows for xp_DirTree

DECLARE

@IsFile BIT –1 if Name is a file, 0 if not

–===== These are object "handle" variables

DECLARE

@ObjFile INT –File object

DECLARE

@ObjFileSystem INT –File System Object

–===== These variable names match the sp_OAGetProperty options

— Made names match so they’re less confusing

DECLARE

@Attributes INT –Read only, Hidden, Archived, etc, as a bit map

DECLARE

@DateCreated DATETIME –Date file was created

DECLARE

@DateLastAccessed DATETIME –Date file was last read (accessed)

DECLARE

@DateLastModified DATETIME –Date file was last written to

DECLARE

@Name VARCHAR(128) –File Name and Extension

DECLARE

@Path VARCHAR(128) –Full path including file name

DECLARE

@ShortName VARCHAR(12) –8.3 file name

DECLARE

@ShortPath VARCHAR(100) –8.3 full path including file name

DECLARE

@Size INT –File size in bytes

DECLARE

@Type VARCHAR(100) –Long Windows file type (eg.’Text Document’,etc)

–=================================================================================================

— Create temporary working tables

–=================================================================================================

–===== Create a place to store all file names derived from xp_DirTree

IF OBJECT_ID(‘TempDB..#DirTree’,‘U’) IS NOT NULL

DROP TABLE #DirTree

CREATE TABLE #DirTree

(

RowNum

INT IDENTITY(1,1),

Name

VARCHAR(256) PRIMARY KEY CLUSTERED,

Depth

BIT,

IsFile

BIT

)

–===== Create a place to store the file details so we can return all the file details

— as a single result set

IF OBJECT_ID(‘TempDB..#FileDetails’,‘U’) IS NOT NULL

DROP TABLE #FileDetails

IF OBJECT_ID(‘FileDetails’,‘U’) IS NOT NULL

DROP TABLE FileDetails

CREATE TABLE FileDetails

(

RowNum

INT IDENTITY(1,1) PRIMARY KEY CLUSTERED,

Name

VARCHAR(128), –File Name and Extension

Path VARCHAR(128), –Full path including file name

ShortName

VARCHAR(12), –8.3 file name

ShortPath

VARCHAR(100), –8.3 full path including file name

DateCreated

DATETIME, –Date file was created

DateLastAccessed

DATETIME, –Date file was last read

DateLastModified

DATETIME, –Date file was last written to

Attributes

INT, –Read only, Compressed, Archived

ArchiveBit

AS CASE WHEN Attributes& 32=32 THEN 1 ELSE 0 END,

CompressedBit

AS CASE WHEN Attributes&2048=2048 THEN 1 ELSE 0 END,

ReadOnlyBit

AS CASE WHEN Attributes& 1=1 THEN 1 ELSE 0 END,

Size

INT, –File size in bytes

Type VARCHAR(100) –Long Windows file type (eg.’Text Document’,etc)

)

–=================================================================================================

— Make sure the full path name provided ends with a backslash

–=================================================================================================

SELECT @piFullPath = @piFullPath+‘\’

WHERE RIGHT(@piFullPath,1)<>‘\’

–=================================================================================================

— Get all the file names for the directory (includes directory names as IsFile = 0)

–=================================================================================================

–===== Get the file names for the desired path

— Note that xp_DirTree is available in SQL Server 2000, 2005, and 2008.

INSERT INTO #DirTree (Name, Depth, IsFile)

EXEC Master.dbo.xp_DirTree @piFullPath,1,1 — Current diretory only, list file names

— Remember the row count

SET @DirTreeCount = @@ROWCOUNT

–===== Update the file names with the path for ease of processing later on

UPDATE #DirTree

SET Name = @piFullPath + Name

–=================================================================================================

— Get the properties for each file. This is one of the few places that a WHILE

— loop is required in T-SQL.

–=================================================================================================

–===== Create a file system object and remember the "handle"

EXEC dbo.sp_OACreate ‘Scripting.FileSystemObject’, @ObjFileSystem OUT

–===== Step through the file names and get the properties for each file.

SET @Counter = 1

WHILE @Counter <= @DirTreeCount

BEGIN

–===== Get the current name and see if it’s a file

SELECT @CurrentName = Name,

@IsFile

= IsFile

FROM #DirTree

WHERE RowNum = @Counter

–===== If it’s a file, get the details for it

IF @IsFile = 1 AND @CurrentName LIKE ‘%%’

BEGIN

–===== Create an object for the path/file and remember the "handle"

EXEC dbo.sp_OAMethod @ObjFileSystem,‘GetFile’, @ObjFile OUT, @CurrentName

–===== Get the all the required attributes for the file itself

EXEC dbo.sp_OAGetProperty @ObjFile, ‘Path’, @Path OUT

EXEC dbo.sp_OAGetProperty @ObjFile, ‘ShortPath’, @ShortPath OUT

EXEC dbo.sp_OAGetProperty @ObjFile, ‘Name’, @Name OUT

EXEC dbo.sp_OAGetProperty @ObjFile, ‘ShortName’, @ShortName OUT

EXEC dbo.sp_OAGetProperty @ObjFile, ‘DateCreated’, @DateCreated OUT

EXEC dbo.sp_OAGetProperty @ObjFile, ‘DateLastAccessed’, @DateLastAccessed OUT

EXEC dbo.sp_OAGetProperty @ObjFile, ‘DateLastModified’, @DateLastModified OUT

EXEC dbo.sp_OAGetProperty @ObjFile, ‘Attributes’, @Attributes OUT

EXEC dbo.sp_OAGetProperty @ObjFile, ‘Size’, @Size OUT

EXEC dbo.sp_OAGetProperty @ObjFile, ‘Type’, @Type OUT

–===== Insert the file details into the return table

INSERT INTO FileDetails

(Path, ShortPath, Name, ShortName, DateCreated,

DateLastAccessed

, DateLastModified, Attributes, Size, Type)

SELECT @Path,@ShortPath,@Name,@ShortName,@DateCreated,

@DateLastAccessed

,@DateLastModified,@Attributes,@Size,@Type

END

–===== Increment the loop counter to get the next file or quit

SELECT @Counter = @Counter + 1

END

–===== House keeping, destroy and drop the file objects to keep memory leaks from happening

EXEC sp_OADestroy @ObjFileSystem

EXEC sp_OADestroy @ObjFile

–===== Return the details for all the files as a single result set.

— This is one of the few places in T-SQL where SELECT * is ok.

SELECT * FROM FileDetails