Dim datatable_default_view As DataTable = DataTable.DefaultView.ToTable
Dim servicenumber As String = datatable_default_view.Rows.Item(e.RowIndex)("Service Number").ToString
If datatable.PrimaryKey.Length = 0 Then
Dim keys(0) As DataColumn
keys(0) = datatable.Columns("Service Number")
datatable.PrimaryKey = keys
End If
Dim datarow_edited As DataRow = datatable.Rows.Find(servicenumber)
Dim datatable_default_view As DataTable = _datatable.DefaultView.ToTable
Dim servicenumber As String = datatable_default_view.Rows.Item(e.RowIndex)("Service Number").ToString
'gets the service number of the selected row[code]....
I've put this code under the DatagridView_CellEndEdit event
The Problem: The 'data_row edited' variable doesn't get initialized when exiting the cell in edit mode using the keyboard (ie: pressing the down/up arrow).If I use the mouse it works as expected. Why is this ?
I am converting DataTables to a generic list and need a quick and easy way to implement a Find function. It seems I am going to have to use a Predicate. Upon further investigation, I still can't seem to re-create the functionality. Private Function ByKey(ByVal Instance As MyClass) As Boolean Return Instance.Key = "I NEED THIS COMPARISON TO BE DYNAMIC!" End Function
Dim Blah As MyClass = MyList.Find(AddressOf ByKey) But I have no way to pass in a key variable to this predicate to do the comparison, as I used to do with DataTable..Dim MyRow as DataRow = MyTable.Rows.Find(KeyVariable) How can I setup a predicate delegate function in VB.NET to accomplish this?
Do not recommend LINQ or lambdas because this is question is regarding .NET version 2.0.
I am trying to program a noise reduction algorithm that works with a set of datapoints in a VB.NET DataTable after being helped with my other question. Basically, I want to take two integers, a coordinate value (yCoord for example) and a threshold smoothing value (NoiseThresh), and take the average of the values in the range of (yCoord - NoiseThresh, yCoord + NoiseThresh) and store that number into an array. I'd repeat that process for each column (in this example) and end up with a one-dimensional array of average values. My questions are:
1) Did anything I just say make any sense ;), and
2) Can anyone help me with the code? I've got very little experience working with databases.
[Code]...
I have three sub tables that I want to process. For each I want to combine the rows, as they are only different by contents in the second column(I want to do the same to the fourth column, later):
'Sub table 1
xx|C201 |02300877 |Samsung |....
xx|C201 |02300877 |Toshiba |....
xx|C213 |02300877 |Samsung
[code]....
p.s. For the fourth column, Manufacturer information , I want to do the same and I'd probably get something like this for the final table:
xx| C201,C213,C606,C619 |02300877 | Samsung
xx| C201,C213,C606,C619 |02300877 | Toshiba
xx| C303, C305,C712 |02301163
xx| C207, C209, C708 |02301165
Dim _tableBackLogs As System.Data.DataTable
Do While i - 2 > 0
_tableBackLogs = Global.DataAccess.GetDataTable("SELECT SubjectID,SubjectName,Grade FROM SubjectPI WHERE RegNo='" & CInt(HttpContext.Current.Session("userName")) & "' AND Status='Fail' AND Semester='" & i - 2 & "'")
i = i - 2
Doing this replaces the previous data in the DataTable. I want to retain the previous data i.e i want the new rows to be added to the DataTable w/o replacing the previous rows.
I am currently using DevExpress 10.2 within Visual Studio 2010. In a previous question I was trying to print the current user view of a DevExpress GridControl with the user's choice of expanded or collapsed master rows and/or group sections. I was told this was not possible at this time. I have now decided to use the following code:
[Code]...
I have a TypedDataTable called CamerasDT which has a composite Primary Key of GroupId and CameraId. I want to use TypedDataTable.Rows.Find(key as object) to return a specific row by GroupId and CameraId. I don't seem to be able to find a way to send primary key to the find function.
View 1 RepliesI've got two data tables with store numbers. I need to find out what store numbers are in one data table that arent in another.say one table A might look like:
34, 35, 39
the other table B may be
34, 35, 39, 45
I need to find the 45 If I use nested For Next I can get matches but anything not a match would show up not just the 45 value as the next progresses.
I have a DGV that has a datasource to load the rows I need for display.
Now, I need to save the selected rows to a DataTable.
binding the DGV. I created the DataTable in my DataSet dsProfiles1 and created a BindingSource - bsDataTableDGV
DataTable:
ClientID Int32 not null PK
ClientName String not null
ProgramNo Int32 Not Null
[Code].....
I have a form with a textbox and a add button. User can write a name down on the textbox and click add button. it will save in a datatable with auto ID. After that, the textbox is cleared and the user can write another name on the text box and click the button. This should add to the existing datatable on memory with existing ID + 1. Show on the gridview. (this is just for display purpose to confirm it works)
I have a datatable like this.
Button1.click() event
Dim name = txtname.Text
Dim dt As New DataTable
dt.Columns.Add("ID", GetType(Integer))
[Code] .....
At the moment I have sometime like the code above. in the real program, it is not just name and it is not just one datatable so i just mock up some code. And this code for aspx.
<asp:TextBox ID="txtname" runat="server">
</asp:TextBox><asp:Button ID="Button1" runat="server" Text="Button" />
<asp:GridView ID="GridView1" runat="server">
</asp:GridView>
I Have a datatable in .net. I need to flip the location of two of them. For example, a datatable that the select statement had an order by priority clause. The user wants to up the priority of a single row by selecting it and clicking increase priority, how do i move a row up (AKA flip two rows)
View 2 RepliesI have this sub :
Private Sub error_out(ByVal line As Integer, ByVal err_col As Integer, ByVal err_msg As String)
Dim ln = t_erori.Rows.Add
[Code]....
I suspect this is because it's trying to add the same row twice.
How can i make this work ? Or what else method could I use to do this ?
I need this datatable because my app is writing some results in there, but any other method to store the results that works with parallel.for would be ok.
I have one datatable tempDT with value :
[Code]...
The problem is I want merge duplicate serial_no into one row which the value of testong adding to new column. I have tried many ways, but I can't find the solution. Here is my code behind :
[Code]...
I have a datatable object, which is populated from a webservice.Apparently, the web service just throws everything (data) back to me. The data which gets in my datatable looks like this:
Dept Code Value
Science ABC 5
Science ABC 6
[code].....
At the moment I use this code but I have 591 rows to delete and it takes forever to loop and delete each row on an individual basis
[Code]...
i need to delete some rows from datatable
i don't know the indexes i have 2 columns to idendify the rows to delete
how to achive this in easy way
i don't want to delete inside loop wat will happen if i have 2 million rows? tats why i don't want to delete indendify the rows and delete in loop
I have a Datatable in my code in vb.net. I need to delete rows from the datatable. The name of my Datatable is "temptable".in my row deleting event of a Gridview control. I wrote code as follows:
In the Row_Deleting event of Gridview:
temptable.Rows.Remove(Gridview1.Datakeys(e.RowIndex).value)
But,it shows an error as follows:
"Cannot cast System.Int32 to System.Data.Datarow".
IDE : VS 2008,Platform : .NET 3.5,Here is my DataTable columns :ID Note DetailI want to write sth like this :
View 8 RepliesI have a simple application that uses a database to store usernames and passwords.I have a hidden control that, when activated,should clear all usernames and passwords from the datatable.Then, one admin account is added. I have tried the datatable.clear method BUT while it throws no errors, it doesn't clear the datatable.I have also tried the datatable.reset method, with the same problem. I am now trying this method:
Dim row As DataRow
For Each row In Authenticate.Logins
row.Delete()[code]....
I'm trying to set the same value for all rows for a single column in a datatable without using for loop. Any faster methods to achieve the same.
View 2 Repliesam just curious to know...which is the better or more efficient way of these two?
Note: tblOD is a DataTable
For dtrows As Long = 0 To tblOD.Rows.Count - 1
dgv1.Rows.Add(tblOD(dtrows)(0), tblOD(dtrows)(1), _
[code].....
Way to access datatable rows
[code]...
I have a datatable and I want to create a text file using this datatable. I want that each row of the newly created text file is unique. If there is a duplicate row, then it should add * to both rows ( duplicate rows)
I am using following code:
Dim str As String
For Each row As DataRow In dataTable.Rows
str += row(1) ' This is text data
[Code]...
I have a DataTable which I want to check if values in three of the columns are unique. If not, the last column should be filled with the line number of the first appearance of the value-combination.
[Code]...
I solved this by iterating the DataTable with two nested for loops and comparing the values. While this works fine for a small amount of data, it gets pretty slow when the DataTable contains a lot of rows.My question is: What is the best/fastest solution for this problem, regarding that the amount of data can vary between let's say 100 and 20000 rows? Is there a way to do this using LINQ? (I'm not too familiar with it, but I want to learn!)
i want to make a datagrid with 2 columns and many rows
the columns i want to have databinding with a datatable
i want the 1 row 1 column of datagrid have data from 1 row of datatable
i want the 1 row 2 column of datagrid have data from 2 row of datatable
[code].....
I am new to vb.net and I am trying to query a database and print out the records in the row to the console window. I got it to work, but I have a feeling that there is a more concise way to do this. One thing that I am sure is wrong is that I had to convert the dataset to a datatable to be able to retrieve the values. Is that correct? Could you take a look at the code below (especially the for loop) and let me know what I can improve upon?
[Code]...
I am trying to delete rows from datatable using code below,
View 10 RepliesI am trying to summarize a datatable based on a primary column and then add certain columns. For example this table
col-1 col-2 col-3
1 AA 2
2 BB
[Code].....
This simply doesn't do anything becuase it thinks the target table doesn't have a primary key.
i want to read table row by row i have table with two columns but i want to read the first column only row by row her's my code
Dim col As String = "SELECT users.user1,users.valueid FROM users"
Dim cmd As New OleDbDataAdapter(col, CON)
Dim ds As New DataSet
[Code].....
