I am doin a library management project for my college using vb.net and Ms Access as database. I am getting a error No data exists for the row/column. wen i try to select a value in 1st combobox . The first 3 values are working perfectly wen i click on 4th i get error heres da code
Private Sub ComboBox1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ComboBox1.SelectedIndexChanged
Why am I getting this error, I know there is data there, the code I am using is: Dim iMaxFields As Integer = oDataReader.FieldCount - 1 Do sLine = "" For iColCounter = 0 To iMaxFields sColOutput = oDataReader.Item([iColCounter]).ToString() sLine = sLine & sColOutput [Code] ..... Basically I just want these details put into a HTML table.
I have a windows service which fetches data from various datasources and build a XML file and send it to a webservice. For example first I will get customer details from Oracle Database and build the XML file and then the SQL Server database and build the customer details XML. I am planning to use the same function below to build the customer object irrespective of what the datasource is. But dr("age") column is not available in SQLserver datbase How can I check if a column exists or not.[code]
I want to insert a value from loop in datarow so before entering value in datarow, i want to check that a perticular column NAME exist in table or not...please tell me how can i check it. (vb.net preferred).
I have a datagridview which is populated from a datatable. This works fine. But if i run it more then once i get a column name "example" already belongs to this datatable. Ive tried everything to clear all the columns of the datatable and the gridview but still the same
I have a function in VS2008 VB.NET that creates a dataset and reads field values from that were loaded from a SQL Server 2008 database tables. The tables are from varied sources and in some cases particular column/field names are different. Some use a long name; others use a short name. I need to determine whether a short name or a long name is being used.Pseudo code:If row("ShortName") Exists then ReadDataFrom r("ShortName").ToStringElse ReadDataFrom r("LongName").ToStringEnd If
How would I determine if a particular column name exist in a dataset or datarow?
I am creating a program which searches saved .htm files for the source codes. I get the source code and do manipulation on the code to pull the values I need into a datagridview.
Is there anyway to search a datagridview column to see if a value exists first, so no duplicate rows of data will be added? I was thinking of making access table and linking the datagridview to it, but i'm not sure how to set the database links up with code (other than the gui), and then still search the column so I don't put in duplicate rows.So far, I have only come up with the way to add the data row by row...
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim IMsku As String Dim IMskuitna As String
I have two tables, dt & dtResults.dt contains 3 columns named: vchInstrumentAnalyteID, bintAnalyteCodeID, & vchAnalyteCode dtResults contains several columns including the columns in dt
I want to get vchInstrumentAnalyteID from the first row in dt and test if it exists in the vchInstrumentAnalyteID column in dtResults. If it exists, I want to use that value from dt to filter rows in dtResults and fill all the filtered rows with data from that row in dt. Then loop to the next row in dt.
I have this code, which is close to what I need, but I can't get it working.
' put analyte data in results table For Each drA As DataRow In dt.Rows If
I have been messing around with this for a little while and I don't know where I am going wrong. No idea why I should be getting an error. Hopefully it is something simple I have over looked. The image shows the error message, the table I am selecting from, and the method that I am calling.
I have been on MSDN about this and searched but it's not quite telling me what I'm after. I've extracted a list of file names from an Excel spreadsheet and want to check whether they all exist in a directory which a user can select in a text box. It feels like I'm nearly there with it but currently my listbox is displaying everything, I want it to just show the files that are missing. I'm a beginner so I'm not exactly sure if I'm even telling it to compare the two things properly, I've tried a couple of ways of checking if a file exists but neither seem to work.[code]
This is my programs complete code, the only problem is i want to fix the amount of decimal places that show up in my gridview. The problem is if i do this on the asp side the location of the column gets thrown off and the column is duplicated. I figured if i just remade the table on the asp side it would work only problem is if i remove the sql for that particular column the asp side column cannot get data.
I want to merge or import a column of data from one data table created in VB.NET to another data table's 'same-named' column.The destination data table has all the required columns created before hand but the source data table contains one column at a time, whose name is the same as that of one of the columns in destination data table.Whatever coding I have done for the same till now, results in blank rows at starting. The destination data table looks like this:And I want it to be displayed it as:
I have a VB.NET WinForms application. While adding a new data source, it is giving "An item with the same already been added" on the Add Data Source wizard form.
The application does not contains any existing data source.
What could possibly be causing this error, and how might I go about resolving it?
SQL Server has a Data Type of "Float". Visual Studio has a Data Type of "Decimal". In other words, if I have a variable in a VB.Net app that is defined as a "Decimal" ...can I move that value into a SQL Server Data Table column defined as a "Float"?
I have a listview that has data in 4 different columns. It's just a quick phone storing project to keep "tuned up" on my programming.This is what i have to add the data into each column.[code]I need help finding the data in the second, third, and fourth column because that above is just returning the data in the first column.
I am using VB.net Express I need to produce a chart so am using MSchart object.I am using the following code to try to add data (2) to column 1 of a series
Me.Reject_Chart.Series(0).Points.AddXY(1, 2)
I do not get an error immediately but then before the form can be refreshed I get a stack overflow.how to I set this data?
So I have a text box in a form. The test box needs to take the value entered and insert it into a column within a row in MySQL. I know it's connecting to the MySQL online, I have a message box telling me so upon a successful connection. I'm just having problems adding the value. Here's my code: Public Class frmOptions Dim ServerString As String = "server=db4free.net; Port =3306; user id=dailylogmain; password=XXXXXXX; database=dailylogmain;" Dim SQLConnection As MySqlConnection = New MySqlConnection
Private Sub frmOptions_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
'search Male Dim cmdTextName As String = "SELECT isnull(Count(Gender),0) as TotalMale FROM tblStudent WHERE (Gender = Male)" Dim sqlcmdName As New SqlCommand(cmdTextName, New SqlConnection(GetConnection)) sqlcmdName.Connection.Open()
[code]....
Am trying to count the number of male in my table however when i try to run using this code it pops an error which is "invalid column name Male" what seems to be wrong with my statements?
I have a data grid view that contains several columns. The first column is the only column I care about and it contains Result IDs. The view may be filter from time to time. I want to get the Result IDs from all the visible rows and put them into a table variable so I can use ADO.Net to send that table to a SQL Server stored procedure. I currently use a loop (see below). Is there a way to do this quicker without a loop? I'm new to VB.Net and I was hoping .Net would have an impressive method to do the same thing the loop below is doing.
Private Function prvfnc_GetResultIDs(ByVal dgv As DataGridView, ByRef dt As DataTable) As String Dim rw As DataRow
The user enters information into a textbox and I would like to reflect these changes on the database. So say there is a value of 50 in the textbox and the user just deletes this and it is now "". When I try to update the database I receive an error as it expects a type of double. However, simple appending a 0 here when a value of "" is encountered will not work for me as I have a universal function to handle all of my updating needs. How would I go about determining the type of field I am dealing with (int, double, varchar) of the data table which I currently have in memory
I am trying to parse a file generated by LGA Tracon that lists the position data for aircraft over a given time frame. The data of interest starts with TRACKING DATA and ends with SST and there are thousands of entries per file. The system generating the file, Common ARTS, is very rigid in its formatting and we can expect the column spacing to be consistent. Here is an image to preserve the exact formatting Here is a reduced text file.
I need to add data into a multi-column list, manually, in codes. I am using VB Express 2008. Could someone please hint me on how to do this with the following controls:
The ListBox or the ListView The Grid (I think it is the DataGridView)
Or anyother simple way of doing the stuff. All I want is simplicity.
I am trying to add data to a access datatable column I am using a richttextbox to fill in any data but when i save it to a column in a database and if there are more chars then 255 then i get an error (try to enter more then column lenght) anything under 255 is working fine the column in access = type of 'MEMO' so no limited to 255 it's the hystory to send that is giving me the problem
Dim history_to_send As String Dim day_to_send As Date Dim ID_to_send As Integer
if you could possibly point me to the right direction, that would be great. i have tried researching about this but found no solution.i have a 2d array which holds student name and 3 grades (eng, maths, science.)student array (24,3)Now, i would like to use the data which is held within the array to create averages.I need a total class average for: maths column, eng column, and science. I also need an overall average for all subjects.the code i have used, so far, brings some odd results.