I'm trying to validate the contents of a datagrid cell against the values in a Dataset:
VB
Private Sub dgOperator_CellValidating(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellValidatingEventArgs) Handles dgOperator.CellValidating
[Code]....
I just read about DataSet in VB.NET, it uses disconnected concept. My question is: if my apps has "List All" button that query data from 1 table in the database, and that table has "very very very" many rows, so my DataSet will be filled with those data and eat up memory. Can I limit the data that being put to the DataSet from that query? But I want to be able to retrieve the next data from the same query if the user want to see it?
For example:
I have 1000 rows in my database, and i query all of them. But I just want 200 rows being inserted to my DataSet, but if the user want to see rows number 201 and so on, I want to be able to retrieve the next 200 rows, and so on. So it just like cutting those data into a group of 200 rows. Can I do this with the concept of "disconnected" of the DataSet?
validating a datagrid coloumn..,i want only alphanumeric values.,symbols like -,+..etc were not allowed..folliwing is the code wht i have.,but it allows only alphabets but not numerals.
[Code]...
I have a combobox that is bound to a dataset. The dataset has 3 columns of data. at any given time there could NOT be any data in the dataset.
When someone selects an item from the box I want to store data from 2 of the columns of the row they selected.I do the 'store' in the selectedindexchanged event.
so currently I am assigning each column/row value to a property from a datarowview i get from combobox.selecteditem.
Code:dim column1 = drv.row.item(0).tostringdim column2 = drv.row.item(1).tostring
But I am getting NullReference exceptions all over the place when there is not data.So i have to wrap it all in a try catch and assign nothing to the properties when the Null exception fires.
I want to also validate that there is a selection made. There must be a selection made if there is no data in the DS fill it.I do this in the combobox validate event.
It just seems like there is a better way to check for no data coming from the combobox.
I wish there was a way to do some sort of .count on the datarowview you get back from the combobox.selecteditem but anything i have found also gives a null ref exception if used.
Also what is used to programmaticly change the selected item?
I have a combobox that is bound to a dataset.The dataset has 3 columns of data.at any given time there could NOT be any data in the dataset.When someone selects an item from the box I want to store data from 2 of the columns of the row they selected.I do the 'store' in the selectedindexchanged event.so currently I am assigning each column/row value to a property from a datarowview i get from combobox.selecteditem.
Code:dim column1 = drv.row.item(0).tostringdim column2 = drv.row.item(1).tostring
But I am getting NullReference exceptions all over the place when there is not data.So i have to wrap it all in a try catch and assign nothing to the properties when the Null exception fires.I want to also validate that there is a selection made. There must be a selection made if there is no data in the DS fill it.I do this in the combobox validate event.It just seems like there is a better way to check for no data coming from the combobox.I wish there was a way to do some sort of .count on the datarowview you get back from the combobox.selecteditem but anything i have found also gives a null ref exception if used.Also what is used to programmaticly change the selected item?.selecteditem.selectedtext.selectedindex.selectedvalue?
I am having a problem with the cellvalidating event constantly firing when the datagrid is refreshed (since the trigger that fires the event is the originally selected cell losing focus).I would like to remove the event handler for this at certain points of my code so that it does not fire but the examples I have come across on MSDN don't appear to do anything, so I guess I must be doing something wrong.[code]
View 1 RepliesHow can one search for multiple items at once and display the result in a datagrid? for example, i want to search for multiple mobile numbers (in sql server database)at once and display the found numbers and their corresponding names.
View 4 RepliesI have two text box(Start Value and End Value), one datagridview and a search button SQL script= Select id, ContactName from Customers where id between 1 and 5 I want a scenario where when I enter the start value 1 and end value 5 and click the search button it will run the above query and display the result in the datagrid view.
View 4 RepliesHow do you compare the contents of the textbox with result of the dataset?
View 4 RepliesI have a small section of a windows form that allows users to select when a customer should be called (i.e. day of the week, time and inbound or outbound)When the form is loaded I will extract the information using a dataset and bind to form controls. I want to use a combo box for call stautus - inbound or outbound - however wish to give the user the choice at runtime.My thoughts are I would need to set a static list (so the user could choose) and set the default or displayed value to the info the dataset has extracted.This code to select the index doesnt work when I am comparing the dataset result to the "Outbound" string even though I am using the ToString method.
Private Sub TestTelesalesForm_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Me.Telesales_DEV004016TableAdapter1.Fill(TelesalesDataset1.Telesales_DEV004016)
Me.comboCallStatus.Items.Add("Outbound")
[code]....
Lets say i have a class Employee which cotains two propeties (Name, Year) I have another which basically contains list of Employee object i.e EmployeeList.[code]...
View 4 RepliesI have a table in a data grid the columns are bound to the columns...
SQFT QTY WIDTH LENGTH
i also have added into the datagrid an unbound column called Yeild%.what i'm trying to do is the following formula
SQFT / (QTY * (width * length / 144) and have the result return the answer in the unbound yield column for that row represented as a percentage
So if SQFT = 178 QTY = 2 Width = 144 Length = 102 answer would be 0.87 (rounded)
so this would be 87%
I am writing below code for validating compulsary field account no. in form.User's requirement is set focus back on field when error comes :
If txtAccountNo = "" Then
MessageBox.Show("Account no filed can't be left empty")
txtAccountNo.SetFocus
Exit Sub
End If
It's working properly. But suppose user don't want to fill form and exiting from application.Message box keep on appearing till user enters account no.
I need a way to read an xml file into a datagrid without using a dataset. I realize this is probably the accepted procedure, but it forces me to change a lot of existing code if I do.
View 3 RepliesI have tried googling so much that I have given up trying to look. I am trying to display a dataset in a wpf datagrid. After that I am going to need to display the individual column value in textboxes. I can then change the value in those textboxes and pressing, say, a commit button, to commit the changes to a database. Here's the code I have so far.
Dim con As New SqlConnection
Dim dbConnString As String
Dim ds As New DataSet
[code].....
I'm populated my datagridview with data from my database - directly coded to update. I now want to export this data to excel or .csv file. I have found out how to export it from a dataset but not a datagrid. How can I populate a DataSet from my DataGrid? [code]
View 3 RepliesMy problem is that I can't populate a datgrid with the contents of a dataset. Having searched for the last few days to try and resolve this, I have given up and thought I would try here. I am using Visual Studio 2010 and attempting to create a WPF application. As you can tell from the code I am very new to this and any suggestions for improvement will be most welcome. I can see that the dataset is populated ok via the visualizer, I have a datagrid 'dgBOM' which I want to display the results. A popular solution in my searches was to add '.DataSource' but when I type the '.' after dgBOM the Datasource option is not there.
Code:
Public Sub Connect()
Dim cn As OleDbConnection
Dim cmd As OleDbCommand
Dim dr As OleDbDataReader
[Code].....
I have a datagrid that I use to display data from a SQL 2000 table. I am trying to write back any changes the user makes to the datagrid data back to the original table but don't know the proper method to do this.
Here is the code that populates the datagrid:
Dim TheDatabase As System.Data.SqlClient.SqlConnection
Dim ConnectionString As String
Dim cmd3 As New SqlCommand
Dim Adp3 As New SqlDataAdapter
[Code]...
I could use some suggestions on how to code the write back command that will allow the user to change the data in the datagrid and have those changes be written back to my tAdjustment table.
I am binding a dataset (dsTest) with a table called "TempResult" to a datagrid (DatagridView1).The purpose of the datagrid is to display test labels (set elsewhere in the software) and to allow the user to enter results into an empty column titled results.To achieve this I've filled the dataset with the required test labels then added a column called "Result" with a default value of 0.00.The user can enter numbers into the "Result" column on the grid then click a button "ADD" to update the changes to the datatset,When I first open the form the datagrid shows the correct information and any changes made to the Result column are updated correctly - all is well.
Private Sub Add_Results()
Dim ResultColumn As DataColumn
Dim Rows As Integer
Dim i As Integer
[code]....
If I close the form and open it up again (i.e. the user wants to add more results) the datagrid shows the results entered the last time the form was use and any changes made to the grid are not updated and the form won't work again until the software is reloaded.
It was written in vb6 and im trying to rewrite it in vb.net. I've completely stripped the program down from all the unneeded fancy addons and now just have the needed code to run it. The program retreives the records, but does not populate these records onto a datagrid.
Heres my Form code (Form1)
Imports ADS_SQL_TEST_VBNET
Public Class Form1
Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
[Code]...
I think the problem lies within the LoadDataBound() Sub routine, but I can't say for sure since I was unable to fix this myself.
basically i have a form with a datagrid set to readonly. i have 5 textboxs.when a cell is clicked its value in the row is output to the following textboxs on the form As the datagrid is set to readonly i want a user to be able to update table/ dataset via the data enter using the textbox, then to be re-fill the datagrid with updated data.....If that makes sense.i have tried looking many examples that date back from 2006 to 2008, has there been any change in .net framework that can make this similar.
Private Sub DataGridView1_CellClick(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles maingrid.CellClick
Dim i As Integer
i = maingrid.CurrentRow.Index
[code]....
I consider myself a very patient guy with a whole lot of determination to get things working within say, a program i'm working on. However, I feel that I am only wasting precious time that I could be using to actually gain knowledge in something rather than hitting my head against a wall accomplishing nothing. It was written in vb6 and im trying to rewrite it in vb.net. I've completely stripped the program down from all the unneeded fancy addons and now just have the needed code to run it. The program retreives the records, but does not populate these records onto a datagrid.
form1
Imports ADS_SQL_TEST_VBNET
Public Class Form1
Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs)
[Code].....
im trying to rewrite it in vb.net. I've completely stripped the program down from all the unneeded fancy addons and now just have the needed code to run it. The program retreives the records, but does not populate these records onto a datagrid.
form1
Imports ADS_SQL_TEST_VBNET
Public Class Form1
Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
[code]....
I think the problem lies within the LoadDataBound() Sub routine, but I can't say for sure since I was unable to fix this myself.
I have a table with two columns (id and number1). How can i get from the datagrid or the dataset the data of one column (number1) in one variable?
View 7 RepliesI m working on vb.net ado.net oledb, I have also added datagrid Control to my form
for retriving database from .Mdb file i used following code
'decleared Name Space
Imports System.Data.OleDb
'Dicleared Variabls in Class Form1
[code]....
how to move current record in datagrid, i mean when i press Next record button then datagrid's data (table) also should move to next record or when i click any record in datagrid, then the current record of dataset also should move to clicked record of datagrid, so that i also may see datagrid's clicked record in textboxes in short i want to use default feature of vb6's ado control, when we bind datagrid with ado control, it worked autometically, both data grid and adodc wer connected each other at a time, so that moving next record also apears in datagrid.
I think I fried my brain. Something so easy and I can't figure it out. I have a windows form with a datagrid and a dataset and some textboxes.I have a button that populates the textboxes with the selected row from the datadrid. That works.The user then makes changes to those text boxes.Now I would like to update the dataset with those new values and can not figure it out.If you could please give me some sample code,
View 9 RepliesI am creating an app to grab data from excel and preview in datagrid. From the datagrid I want to be able to save to a sql table. I have the excel data in a gridview via a dataset. What I am having trouble with is the sql statement. I know how to insert data, but I can't work out how seperate the data in the dataset to pass it into individual Values of the insert statement. Or should it be done another way? NOTE: I is not essential that the excel data be previewed in the gridview if this would make life easier for me.
Here is my code so far:
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
'Grabs data from excel sheet and stores it in datagrid.
Dim ds As New DataSet
Dim da As OleDb.OleDbDataAdapter
Dim con As New OleDb.OleDbConnection
[Code] .....
I am currently having a headache on how to solve this problem that i am facing. here is the situation: I have a combobox and a list box on the main form. The combobox will get the data from the ms access database. In the database, i have the details of a person's IC, Name and DOB say for eg on one entry I have D215311523C,SHAWN,13/04/1987 So now, my combobox on form load will show the list of dates in the database to allow the user to search base on the date itself by clicking on the selected date. So when the user clicks on the particular date say 13/04/1987, people in the database whose birthday is 13/04/1987 will be shown on the listbox.Meaning to say if i have 3 entries whose dates are the same 13/04/1987, 3 entries will appear. If there is only two entry, then two results will be shown. But now, when i do a single click on the date, one result will be shown. That is correct. But the problem is when i click on the same date again, three of the same results will be shown on the list box. that is it will display : 13/04/1987 13/04/1987 13/04/1987 which is not the case. Then it will show more duplicates of the same results if i click more times on the same date which should not be the case.
Dim n As Integer
Dim numbers() As Integer
Dim StartFrom As Integer
Dim EndAt As Integer
[code].....
I am using a datagrid in my where i am having four columns. In first column the parameter values are entered and in the second column measured value is entered and in third column the nominal value is entered.Inthe fourth column the result is displayed by subtracting the measured value and nominal values. I am doing this calculation in Datagrid cell validated event. What i want is,there will be many rows in the grid,when typing the value in the third column the corresponding result will be displayedin the rowof theresult column,save button will be displayed while the form loads,when the calculate part is completed that is there should not any cell of the resut column empty then i should enable the save butto.
View 2 RepliesI am encountering the following issue So i have a device that sends stuff at the serial port, i then parse it and put it into an array of bytes like that:
Dim HCI_Command_Rcvd_Byte() As Byte All good till here What i wanna do is make an array and put this result every time the serial port gives me a new result, for example:
[Code]...
Basically what i wanna do is let the port parse the messages, fill in the array with the result at an empty spot in this array and then i will have a separate thread that will look in into this array in each non empty space and after it looks into the non empty space it will use or discard the info and also mark this space as empty (after it checked)