I added the table in TableCell
Dim rSkala As New TableRow()
Dim cSkala As New TableCell()
cSkala.Controls.Add(New Table())
rSkala.Cells.Add(cSkala)
How can I use this table now? I want add to the table rows and cells, but this table haven't name
You must assign programmatically the ID of the control:
Dim rSkala As New TableRow()
Dim cSkala As New TableCell()
Dim newTable as New Table()
newTable.ID = "myID"
cSkala.Controls.Add(newTable)
rSkala.Cells.Add(cSkala)
At this point your table has an ID to be referenced (es. with FindControl("myID"))
Related
I have a DataTable with multiple columns in it, and i would like to import some of the columns with the data of every row of it to a DataGridView in VisualBasic.
Can you please help me?
Your question is very very generic. In either case here is a sample.
'Create a new datatable
Dim table2 As New DataTable
table2.Columns.Add("Name")
'loop through your existing datatable - add the records to the columns you want
For Each dr As DataRow In Table1.Rows
Dim R As DataRow = dt.NewRow
R("Name") = dr("TABLE1_COLUMNNAME")
dt.Rows.Add(R)
Next
'turn the new datatable into the datagridview.
DataGridView1.DataSource = table2
I am trying to add a checkboxlist and then add a new checkbox to every row in an ASP.NET table:
Dim cbList As New CheckBoxList
cbList.ID = "cb_list"
Dim c1 As New TableCell
Dim c2 As New TableCell
Dim r As New TableRow
c1.Controls.Add(New LiteralControl(dr.GetString(1)))
c2.Controls.Add(cbList.Items.Add("new cb")) 'error: expression does return a value
r.Cells.Add(c1)
r.Cells.Add(c2)
modaltable.Rows.Add(r)
The c2.Controls line returns the following error:
"expression does return a value"
I can't seem to get round this problem. Any help is appreciated!
I'm having a problem populating a child gridview using a function I define. I keep getting the error "Object reference not set to an instance of an object". What am I doing wrong? Am I using the FindControl function incorrectly? It doesn't seem to find the child gridview.
Sub RecordsByZip()
Dim DBConn As New SqlConnection(Application("DBConn"))
Dim gv1 As GridView
gv1 = grdTotal
Dim gv2 As GridView
gv2 = DirectCast(gv1.FindControl("grdChild"), GridView)
Dim ZipCode = lbZip.SelectedItem
For Each ZipCode In lbZip.Items
If ZipCode.Selected = True Then
Dim cmdZip As SqlCommand = New SqlCommand("spPICAInsertTotals2", DBConn)
cmdZip.CommandType = CommandType.StoredProcedure
strZip = ZipCode.Text
strUser = Session("User")
Dim Zip As New SqlParameter("#Zip", SqlDbType.VarChar)
Zip.Value = strZip
cmdZip.Parameters.Add(Zip)
Dim UserID As New SqlParameter("#UserID", SqlDbType.Int)
UserID.Value = strUser
cmdZip.Parameters.Add(UserID)
DBConn.Open()
gv1.DataSource = cmdZip.ExecuteReader
gv1.DataBind()
gv1.Visible = True
DBConn.Close()
End If
Next
btnExport.Visible = True
lblmsg.Visible = False
' Dim DBConn = New SqlConnection(Application("DBConn"))
Dim cmdCounty As SqlCommand = New SqlCommand("spPICAInsertTotals", DBConn)
cmdCounty.CommandType = CommandType.StoredProcedure
'Dim gv As GridView = TryCast(e.Row.FindControl("grdChild"), GridView)
strUser = Session("User")
Dim UserID2 As New SqlParameter("#UserID", SqlDbType.Int)
UserID2.Value = strUser
cmdCounty.Parameters.Add(UserID2)
DBConn.Open()
gv2.DataSource = cmdCounty.ExecuteReader
gv2.DataBind()
gv2.Visible = True
DBConn.Close()
btnExport.Visible = True
lblmsg.Visible = False
lblInstructions.Visible = False
End Sub
First of all . . .
Just as a disclaimer, I normally use repeater controls instead of gridview controls.
But this may help you . . .
I can tell you that with repeater controls, if you want to find a nested repeater then you must look for them inside the item of the parent repeater to which they belong. Essentially, what you are trying to do with the code above, is find grdChild when there might actually be several grdChild (it is a nested gridview, after all). I'd be willing to bet this is where you're object reference error is occurring.
In other words, if you want to find the nested repeater with the ID nestedRepeater, and you know it is located in the first item of your main repeater (which in this case I've assigned to the myRepeater variable), you can do this:
Dim myItem as RepeaterItem = myRepeater.Items(0)
Dim Rep2 as Repeater = myItem.FindControl("nestedRepeater")
Using SqlDataAdapter and a DataSet (recommended)
Dim sa As New SqlDataAdapter(cmdCounty) 'Initialize the SqlDataAdapter and assign the SqlCommand object to it.
Dim ds As New DataSet() 'Initialize the DataSet (we will bind this to the gridview)
Try 'The Try/Catch statements help you to handle errors.
cmdCounty.Connection.Open() 'Open the connection to the database.
sa.Fill(ds) 'This statement uses the SqlDataAdapter to easily execute the SqlCommand (using the query specified in the SqlCommand object) and . . .
'. . .use that data to fill our dataset.
cmdCounty.Connection.Close() 'These statement close the connection and dispose of the SqlCommand object. Note: You may only need the dispose command.
cmdCounty.Dispose()
Catch ex As Exception
'Catch your error here.
cmdCounty.Connection.Close()
cmdCounty.Dispose()
End Try
gv2.DataSource = ds 'Set the datasource for your GridView control.
gv2.DataBind() 'Bind the data.
Using SqlDataReader and a DataTable
According to your comment, you're code is breaking when you assign the gridview to the cmd.ExecuteReader.
You will need to access your data using a method like this:
Dim rdr as SqlDataReader = cmdCounty.ExecuteReader() 'Declare the SqlDataReader and set it to handle your SqlCommand.
Dim dt as New DataTable 'Initialize a new DataTable. This is where we will place the information we read using the SqlDataReader.
'Make sure you add the columns...
dt.Columns.Add("firstColumnName") 'Create a column for each field you will be retrieving data from.
dt.Columns.Add("secondColumnName")
Dim r as DataRow 'Declare the variable r as a DataRow.
'You may want to insert the line "If rdr.HasRows Then" to check if any data was pulled before attempting to read it.
While rdr.Read() 'Loop through each row in the reader.
r = dt.NewRow() 'Set r to equal a new DataTable in the DataTable we created. Note: This does not actually add the row to the table.
r("firstColumnName") = rdr("firstColumnName") 'Set the values of each column in the current DataRow to equal their corresponding data read from SQL.
r("secondColumnName") = rdr("secondColumnName")
dt.Rows.Add(r) 'Add the DataRow r to the DataTable.
End While 'Loop back until there are no more rows.
gv2.DataSource = dt
gv2.DataBind()
Both of these examples assume you have already created your SqlCommand object and have assigned a working SQL query string and Connection object to it.
I am new to asp.net and here I am trying to populate a single text box with a value from database.
I have created this code but not working:
Try
Dim MyCon As New SqlConnection("server = servername; uid = sa; pwd =abc; database = master")
Dim MyCommand As New SqlCommand("Select empFirstName from Employees where empid=2")
MyCon.Open()
Dim MyReader = MyCommand.ExecuteReader()
While MyReader.Read()
Dim sqlda = New SqlDataAdapter()
Dim dt As New Data.DataTable()
Dim ds As New Data.DataSet
sqlda.Fill(ds)
TextBox1.Text = ds.Tables(0).ToString
MyCon.Close()
End While
Please correct the code and tell me where I am wrong.
Kindly suggest me a link if any to read more on this topic for beginners with example.
Try this sample, it will work for you http://geekswithblogs.net/dotNETvinz/archive/2008/09/12/bind-textbox-and-label-control-with-data-from-database.aspx
ds.Tables(0)
will return a DataTable
If you want to get the tablename, write this instead:
ds.Tables(0).TableName
If you want to get value returned, write this kind of code:
ds.Tables(0).Rows(0).Item("empFirstName")
This will store only the 1st row from the database
TextBox1.Text = ds.Tables(0).Rows(0)(0).ToString();
Row(0)(0) indicates to get the 1st row from the 1st column
If the query is returning more than 1 rows then u need to iterate the data table and store it in a List(Of String) instead of an array as you don't know the number of rows returned from the query
Dim EmpFirstName As New List(Of String)
Dim myRow As DataRow
Dim myColumn As DataColumn
For Each myRow in dt.Rows
EmpFirstName.Add(myRow(dt.Columns(0)))
Next
In my Grid View ,When a button is clicked,i want to insert that row in to database and at the same time make the row invisible in the Grid View.
I can insert in to database but can't make the inserted row invisible.
Dim PayID As Integer = (e.CommandArgument)
Dim EmpID As Integer = (e.CommandArgument)
Dim EID As Integer = CType(Dg1.DataKeys(EmpID).Values("EmpID"), Integer)
Dim PID As Integer = CType(Dg1.DataKeys(PayID).Values("PayID"), Integer)
cmd.CommandText = "Insert into EmployDetails(EmpID,PayID,PayDate)
Values(" & EID & " ," & PID & ",GetDate())"
cmd.ExecuteNonQuery()
Thank You
You might need to bind the GridView to a DataView instead of a DataSet. Then when you add a row update the DataView to exclude the new row.
After insering your row to db, you should remove the related record from datasource (datatable, dataview) and rebind your gridview.
EDIT :
After your Insert operation :
1. take your remove the related row from your datasource :
Dim insertedRows As DataRow() = myDataTable.Select("ID = " & id)
For Each dr As DataRow In insertedRows
myDataTable.Rows.Remove(dr)
Next
2. And after that re-bind your gridview :
gridView.DataSource = myDataTable
gridView.DataBind()
NOTE : I use a converter to convert codes C# to VB. Hope it's ok.