I am new to ASP.NET. I am trying to display my sql results using a list view. I am using the example for grouping my results by a data field from the 4GuysFromRolla.com website. However, I find the way of grouping the items by a data field to be a bit clumsy. Is there a better way to do it?
Thanks.
Nested ListView - http://mattberseth.com/blog/2008/01/building_a_grouping_grid_with.html
I have never used a ListView, but I did do grouping in a GridView. You can try porting this over to a ListView if you want:
Protected Overrides Sub Render(ByVal writer As System.Web.UI.HtmlTextWriter)
Dim tblGrid As Table = Me.GridView1.Controls(0)
Dim strLastCat As String = "#"
Dim row As GridViewRow
For Each row In GridView1.Rows
Dim intRealIndex As Integer = tblGrid.Rows.GetRowIndex(row)
Dim strCat As String = Me.GridView1.DataKeys(row.RowIndex).Value
If strLastCat <> strCat Then
Dim rowHeader As New GridViewRow(intRealIndex, intRealIndex, DataControlRowType.Separator, DataControlRowState.Normal)
Dim newCell As New TableCell
newCell.ColumnSpan = Me.GridView1.Columns.Count
newCell.BackColor = System.Drawing.Color.FromArgb(61, 138, 20)
newCell.ForeColor = System.Drawing.Color.FromArgb(255, 255, 255)
newCell.Font.Bold = True
newCell.Font.Size = New FontUnit(FontSize.Larger)
newCell.Text = strCat
rowHeader.Cells.Add(newCell)
tblGrid.Controls.AddAt(intRealIndex, rowHeader)
strLastCat = strCat
End If
Next
MyBase.Render(writer)
End Sub
The code creates headers each category. The final version can be viewed here: http://www.truedietreviews.com/diet-reviews/
Related
I am working on a website with VB.NET and ASP.NET. I currently have recurring DropDownLists for the user to provide input.
The design is recurring. These DropDownLists get their values from a database table, Everything with the Web interface is working except for writing these recurring values to the database - that is just to give you some background.
I have set the ID's of each DropDownList like so:
FrequencyList.ID = String.Concat("FreqList", DBReader(0))
That is in a loop while reading the DatabaseReader.
This is what I'm having issues with (please note I simplified the code down to make it easier to read:
Dim i As Integer
DBCommand = New SqlCommand()
DBCommand.Connection = DBConnection
DBCommand.CommandType = Data.CommandType.StoredProcedure
DBCommand.CommandText = "StoredProcedureName"
DBConnection.Open()
For i = 1 To AspectTableLength
Dim ParamFrequencyID As SqlParameter = DBCommand.Parameters.Add("#nFrequencyID", SqlDbType.Int)
ParamFrequencyID.Value = FindControl("FreqList" & Convert.ToString(i))
ParamFrequencyID.Direction = ParameterDirection.Input
Next
The FindControl("FreqList" & Convert.ToString(i)) variable is incorrect because it does not access the value - and adding .SelectedItem.Value does not work.
I got help from a developer.
Dim MyControls As ControlCollection = Panel.Controls
Dim Number As Integer 'this is the same as "DBReader(0)"
For Each MyControl As Control In MyControls
If MyControl.ID Is Nothing Then
Else
If MyControl.ID.StartsWith("Span") Then
Number = Replace(MyControl.ID, "Span", "")
Dim Freq As DropDownList = PanelMain.FindControl(“FreqList” & Number)
Dim ParamFrequencyID As SqlParameter = DBCommand.Parameters.Add("#nFrequencyID", SqlDbType.Int)
ParamFrequencyID.Value = Freq.SelectedIndex
ParamFrequencyID.Direction = ParameterDirection.Input
DBCommand.ExecuteNonQuery()
DBCommand.Parameters.Clear()
End If
End If
Next
DBConnection.Close()
I would like to add a new row to my HTML table and delete the row dynamically using VBScript. Iam new to this can anyone guide me how to do this.
Note that this will be Internet Explorer specific. Might not work on other browsers/
Sub AddRow()
Dim objTable : Set objTable = window.document.getElementById("tableid")
Dim objRow : Set objRow = objTable.insertRow()
Dim intCount, objCell
For intCount = 0 To 2
Set objCell = objRow.insertCell()
objCell.innerHTML = "Content for cell")
Next
End Sub
For delete use
window.document.getElementById("tableid").deleteRow(oRow.rowIndex);
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'm trying to retrieve values using VB.NET from a SQL database. How do I use SqlDataSource.Select()? Is there a way to move the value to a variable that I can use for other things?
I know its kind of scattered and vague but that is the best I can do. I basically need to set a labels text to a value in a table.
This puts the result query in to a DataTable.
DataView view = (DataView)dataSource.Select(new DataSourceSelectArguments());
DataTable groupsTable = view.ToTable();
String value;
foreach (DataRow dr in dt.Rows)
{
// Do something here IE grab the value of the first column
value = dr[0];
}
Repying to last question in comment:
YourTable.Rows(index)(index)
YourTable.Rows(index)("columnname")
I was getting crazy trying to do this simple operation:
retrieving data from sqldatasource and put it into variables that I can manipulate.
At the end, Here the working behind code to do this for VB.NET:
Dim DV As New DataView()
Dim DataTable As New DataTable()
Dim SqlDataSource1 As New SqlDataSource()
Dim VALUE As String
SqlDataSource1.ID = "SqlDataSource1"
Me.Page.Controls.Add(SqlDataSource1)
SqlDataSource1.ConnectionString = System.Configuration.ConfigurationManager.ConnectionStrings("Connection_name").ConnectionString
SqlDataSource1.SelectCommand = "SELECT * from Table"
DV = CType(SqlDataSource1.Select(DataSourceSelectArguments.Empty), DataView)
DataTable = DV.ToTable()
For Each riga As DataRow In DataTable.Rows
VALUE = riga("table_name").ToString
Next
the for each, in this case gets only the first value but you can get any value from datatable and put it into vector, or other strings, so you can control data coming from sqldatasource.
ENJOY
G'day,
I have a RadComboBox control inside of a RadGrid that is displayed when the InitInsert action occurs. I'm using Entity Framework as a datasource & the results contained within this are correct. My problem is that when I use findcontrol it returns nothing.
If e.CommandName = "InitInsert" Then
RadGrid1.MasterTableView.InsertItemDisplay = Telerik.Web.UI.GridInsertItemDisplay.Bottom
Dim query = From myTable In dbEntity.myTables Select myTable.Name, myTable.ID
Dim mineCompBox = CType(e.Item.FindControl("mineCompBox"), RadComboBox)
mineCompBox.DataSource = mineCompQuery
mineCompRadBox.DataTextField = "Name"
mineCompRadBox.DataValueField = "Id"
mineCompRadBox.DataBind()</code>
I'm having trouble finding any answers that reference FormTemplate without it being an edit form. What am I missing? :-(
Thanks.
I don't have my computer in front of me to test it but I'm pretty sure that either:
1) You are not looking at the right controls collection
2) or the RadComboBox is not create yet or has been created but the ID doesn't match
so you cannot find it
Again not 100% sure. Maybe this can help you its a complete example: http://beecy.net/post/2009/01/07/telerik-radgrid-formtemplate-codebehind.aspx (maybe check you markup against this one)
My problem was solved by using an ItemCreated command. An example can be found here:
http://www.telerik.com/community/forums/aspnet-ajax/grid/find-controls-when-using-editcommand.aspx
The code for my situation was:
Private Sub RadGrid1_ItemCreated(ByVal sender As Object, ByVal e As Telerik.Web.UI.GridItemEventArgs) Handles RadGrid1.ItemCreated
If TypeOf e.Item Is GridEditFormItem AndAlso e.Item.IsInEditMode Then
Dim dbEntity As WebsiteEntities = New WebsiteEntities
Dim myQuery = From myTable In myTables Select myTable.Name, myTable.ID
Dim EditFormItem As GridEditFormItem = DirectCast(e.Item, GridEditFormItem)
Dim myCombobox As RadComboBox = DirectCast(EditFormItem.FindControl("radDropBox"), RadComboBox)
myCombobox.DataSource = myQuery
myCombobox.DataTextField = "Name"
myCombobox.DataValueField = "ID"
myCombobox.DataBind()
End If
End Sub