I have already defined in my SELECT statement in TableAdapter to tell it what to do if the parameters are Null:
SELECT a.ID, a.NameID, b.BNameID
FROM a INNER JOIN b
ON a.ID = b.ID
WHERE ((@NameID IS NULL) OR (a.NameID = @NameID))
AND ((@BNameID IS NULL) OR (b.BNameID = @BNameID))
The GUID is the SelectedValue of a ComboBox (cbNetwork) If I execute a Debug.Print on the cbNetwork.SelectedValue, I see:
645b9d20-23eb-469e-9faa-e287600a54f3
However, when I try to execute the Fill method of the DataTableAdapter, I get an error "Specified cast is not valid."
[code].....
I am hardcoding an insert statement to a database, based on certain details a user enters into a windows form. The form has a few textbox and datetimepicker controls for the purpose. This form enters a single row in a single table in the database.The table has a few possible null columns defined, in those cases where the user does not have any data for those columns at that particular time.
I have to provide controls for passing data to those null columns nevertheless. In my case, I have two such columns that accept null values, and two corresponding controls - a textbox and a datetimepicker. The datetimepicker has a checkbox added to it so that if it is supposed to be null it doesn't pass the default current date value, and remains unchecked to explicitly specify that it is supposed to be null. By default it is unchecked.
My code is structured as follows:
Form1:
'the sub referenced here resides in a dll file in my dataaccesslayer code, and in my actual example is referenced properly.
'I have shortened the code here for simplicity
[code]....
Now it gives me an error whenever the code comes to the executenonquery(), and says something to the tune of "SqlDateTimeOverflow. Must be between 1/1/1753 12:00:00 AM and 12/31/9999 11:59:59 PM."
I think the value of 'Nothing' from the subprocedure's paramter is not being assigned to the sqlcommand's parameter as a database NULL, which is what I need to pass to the database.I know instead of using optional parameters I can easily create overloaded subprocedures where one sub allows not passing values where the column(s) is supposed to null and other overloaded subs permit combinations of which column(s) are null or not. But it is simple as long as there is just one, or at the most two null columns in a table. If I have dozens of null values in a table that the user can choose to enter or not in a data entry form?
I have a stored procedure which updates a database using the parameters I supply but I'm having trouble passing a NULL to the stored procedure
The field I need to make NULL is a DateTime field
DB.Parameters.AddWithValue("@date", NULL)
This gives me the error 'NULL' is not declared. 'Null' constant is no longer supported; use 'System.DBNull' instead
[Code]...
Is there a way to choose between different methods and pass one into another method ?
Sub conditionnal_binding(ByVal list_box_reference As ListBox, ByVal list_box_final As ListBox, _
ByVal dico_source As Dictionary(Of String, List(Of String)), _
ByVal my_methode As ??? )
' DO SOMETHING
End Sub
I wrote ??? because I don't know how to call another method inside a method.
I would like to choose between different "sub-methods". Here is how I would like to use my method :
conditionnal_binding(ListBox1, ListBox3, HTML.dico_basic_attribut, best_method)
conditionnal_binding(ListBox1, ListBox3, HTML.dico_basic_attribut, some_method)
conditionnal_binding(ListBox1, ListBox3, HTML.dico_basic_attribut, another_method)
I'm currently working on being able to import a DLL written in Fortran into Visual Basic. I've got all the basics down, so now I'm trying to take it a step further. The title basically says it all, but I'll explain what it is I'm trying to do anyways.
For kicks and giggles, let's just assume I want to pass an object that has three double values in it, possibly representing a point in space in three dimensions. In my Fortran method, I want to take that object, print out the x value, then change the x value to 7.5. Here's my Fortran code that does just that.[code]...
In VB.NET, it is entirely possible to pass an integer as a string parameter to a method without calling .ToString() - it's even possible to call .ToString without the ()'s. The code will run without a problem, VB will interpret the integer as a string without having been told to. In C#, these would cause compilation errors - you are required to call .ToString() and to call it correctly in that situation before it will compile. Is there a way to make the VB compilation process check for the same things as the C# compilation process? Would it be best practice in a mixed team to force this check?
View 3 RepliesI'm trying to use a variable that is simply a list of a list of strings.I've declared it as follows:
Dim iRows As New List(Of List(Of String))
Then I'm trying to pass it as a parameter to another method and I've defined the method as follows:
Public Sub Import(ByVal Rows As IList(Of IList(Of String)))
For Each Row As IList(Of String) In Rows
ImportRow(Row)[code]....
Unfortunately, when I try to run that code I get the following error where it tries to pass my variable to my method.
System.InvalidCastException was unhandled by user code
Message="Unable to cast object of type 'System.Collections.Generic.List1[System.Collections.Generic.List1[System.String]]' to type 'System.Collections.Generic.IList1[System.Collections.Generic.IList1[System.String]]'."
When I change the method definition to use the types rather than the interfaces as follows, it works.
Public Sub Import(ByVal Rows As List(Of List(Of String)))
For Each Row As IList(Of String) In Rows
ImportRow(Row)[code]....
So, is it not possible to use generics with interfaces in this way? It works fine as long as I'm not nesting them.
I have a query in a myTableAdapter that ends with WHERE column IN (@S). This works fine when I use myTableAdapter.Fill(dataset.table, "text") but I can't find any way that works to provide multiple text strings such as "text1, text2" for the IN parameter.
View 1 RepliesI have a table adapter on the data set which is filled by using filter parameter (UserID Field). the filter column is an integer. if i pass one integer value it process perfectly. ie;[code].....i need to fill the adapter with multiple users, so i tried the following code and it gives an error [code].....it gives the error saying "Conversion failed when converting the nvarchar value '1,2,3,4' to data type int.
View 5 RepliesI included a MicrosoftReportViewer to my project:
Code:
Private Sub Report_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
[code].....
I have a table adapter for a fairly sizable piece of data. Now with this data I would like to give the user the ability to change the company name and have this reflected in the form on the drop down list of all of the companies once they have clicked submit. However, in order to do so I currently "Fill" the entire table adapter again to achieve this.Is there any way which I could just re-fill the company column from the database in the same tablea dapter.Here is my code for the sub:
Dim NewName As String = txtNewName.Text
Dim OldName As String = txtOldName.Text
Dim FieldName As String = Me.Text[code]...
I have a View that i am trying to use to fill a TableAdapter with. In my code i fill the table adapter properly the first time, filter my bindingsource and use datarowviews to loop through the rows of data and perform the updates needed (done by a stored procedure). Now the problem is, after these updates take place, i need to fill the tableadapter again so that it reflects these changes. Sometimes the View i am using will have no results, other times it may.[code]This is the exact Error "Timeout expired. The timeout period elapsed prior to completion of the operation or the server is not responding."Okay, you'll notice that i fill my view, then filter those results on the column Number equal to 1. I loop through all those results and update the table my view is created off of. After exiting the loop i hit the second .fill which times out after about 20 seconds. After testing, this time out only seems to occur when MyView does not hold any records.
I use Visual Studio 2010 and sqlserver 2008. All work is done in VB.NET. Also, during debugging, i paused on the second fill, went to Toad for Data Analysts and ran a SELECT * FROM MyView which did not time out and returned the empty result table in about 19 seconds. I have also tried doing a dispose on the tableadapter before the second fill but it has a similar time out. Sorry if this answer seems obvious or something, i'm only an Intern and am still learning the language. That seems to have done the trick, from my understanding that lets it run until it finishes (SQLServer will shut it down if the connection stays open longer than it allows). The ta.fill runs at about the same pace as Toad coming in around 19-20 second mark and does not error after multiple tests.
Unable to create a parameter query using the table adapter wizard to process an access db file. Went online and attempted to create an instance for new adapter with out success, when I click finish the wizard does not like the in the query WHERE (Last_Name LIKE @Last_Name). Also receive a warning that my code contains to many arguments for 'txtLastName.Text' Tried to paste screen
Public Class FindMemberForm
Private Sub FindMemberForm_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
[code].....
I need to create a fillby method that includes a variable. I know how to create the query with known information example:
SELECT CadetPhoto, CaseID, CaseManager, ContractRate, DOB, DormAssignment, FirstName, Gender, GraduationDate, HomeCounty, InductionDate, JBCNumber, LastChange, LastName, MiddleName, PID, Race, RefferingPO, SSN, SchoolID, Shots FROM Cadets WHERE (GraduationDate
IS NULL)
But i need something more like
SELECT CadetPhoto, CaseID, CaseManager, ContractRate, DOB, DormAssignment, FirstName, Gender, GraduationDate, HomeCounty, InductionDate, JBCNumber, LastChange, LastName, MiddleName, PID, Race, RefferingPO, SSN, SchoolID, Shots FROM Cadets WHERE (JBCNumber
= Variable)
Where the variable is passed in when the method is called.
How do I set that variable when writing the select statement?
How do I pass in the JBCNumber when the method is called?
I've got a TableAdapter that could point to one of 2 tables (Live vs Dev) - right now, i'm manually going in and changing the table names when before i publish the project, but it's annoying, to say the least.Is there a way to set the table as a variable / parameter?Basically, I'm looking for the equivalent of:
SELECT @hTable1.*, @hTable2.*
FROM @hTable1
LEFT JOIN @hTable2 ON (@hTable1.PO_ID = @hTable1.PO_ID)
[code].....
TableAdapter.Update(...) Inserts NULL Values in all columns for a new record?
View 4 RepliesI have a method which requires a parameter to be passed in. I would like to use the Addhandler to call the method through a dynamically created button control's click event.
When I include () in the AddressOf, VS complains: 'AddressOf' operand must be the name of a method (without parentheses).
When I exclude the brackets, VS complains: Method '...' does not have a signature compatible with delegate...
My code:
CODE:
I have a form with the following on it [code]then everything works as it should (as long as there is data in the text boxes) If there is one of the text boxes is left empty then an error is returned. The text boxes are not bound and the db is set to allow nulls. Is there an easy way to suggest that if name.textbox is empty then input "nothing" or dbnull etc.I have a lot of text boxes (approx 30) and ideally dont want to write if statements for each one. But will if i have to of corse.
View 2 RepliesI have a TableAdapter I created in the DataSet designer. It contains joined tables and I set it up to automatically generate Insert/Update/Delete commands. I understand that I have to write my own UpdateCommand. I did so, in the DataSet Designer, for this particular TableAdapter.
The issue is that the Update Method is not showing up via IntelliSense, when I attempt to write code like this:
vb.net Dim x as Integer = Me.DPTableAdapter.Update(), IntelliSense does not show the Update Method with the parameters I set up.I created the same exact method with another TableAdapter, in the same manner, and it worked just fine.
I also call EndEdit on the BindingSource, I just did not put it in this post.
Whenever I create a table adpater the wizard does not create and update command. It creates Select Insert and Delete but no Update command. I have a primary key in the data and have completely deleted my dataset and created connection and table adtaer from scratch with still no update command wizard says it will create it but does not.
View 5 RepliesI setup a strongly typed dataset using the DatasetDesigner in VB2010. I am using the TableAdapter.Insert method to add data to an Access table. Before the data is inserted I need to validate the data using the DataTable RowChanging event.
How can I get the DataTable RowChanging event to fire when using the TableAdapter.Insert method?
Here is an excerpt of code I have so far:
When the Insert method runs, it does not fire the datatable RowChanging or NewRow events.
Imports System.IO
Imports System.Data.OleDb
Imports System.Data
[Code]....
I am trying to add a parameter to a sqlDataAdapter. I have tried to use parameters.add() but the adapter is not a sqlCommand. Here is some of my code.
Private Sub convertToCSV(ByVal SqlQuery As String)
Dim Dt As New DataTable()
Dim SqlCon As New SqlConnection("Data Source=db;Initial Catalog=productionservicereminder;User Id=id;Password=pass;")
[Code]....
Basically I am trying to do something like this:
Ada.Parameters.Add(New SqlParameter("@pgid", pgid))
I am trying to add NewRow to the database by using datatable in dataset, but before I do that I want to make sure that row is not already there. I create new row for the datatable I am working with, fill it with information. I fill datatable with the row from database that has the same primary key as my NewRow by using tableadapter.fill method, but when I do that my NewRow that was never added to the datatable is filled with information from database(and not information that I assigned to it). I count rows in my datatable before I fill it and it's 0, so why is my NewRow affected by Fill command? (I am using VB.NET 2005 Framework 2.0)
[Code]....
I am getting an error when I write a value to the database. it tells me "Key cannot be null. Parameter name: key". However the key is an auto-increment value and i'm not even writing to that field. I have verified that there is a value being sent to the SQL. I also created a seperate program that writes the same SQL statement to the db and it writes just fine. I also have other places within the same program that write to the database without any problems.[code]
View 17 Repliesi'm having some problems here.i try to put in some data into sql server by using vb code. the data types are small integer and unsigned tinyint.i would like to assign the value as NULL instead of '0' because my reading takes 0 and 1.i tried in this way.
Dim Ignition As Integer = Nothing
Dim ADCCount1 As Integer = Nothing
Param = New SqlClient.SqlParameter("@Ignition", Ignition)[code].....
when i viewed my sql table i found that the Ignition and FuelRead1 show 0.previously i tried to set the value to NULL but it showed error.What should i assign the ignition and ADCCount1 so i will obtain NULL in database?
Following is the code where i am getting the "Value cannot be null. Parameter name: Key" exception.
I cant see anything wrong in this code.
ReadOnly Property dvMeasurements() As DataView
Get
Dim dvMeasurementsRet As DataView = Nothing
[Code]....
I'm trying to populate my textboxs with data from my database when the user name i
table
users (there is a textbox for each of these fields)
password
[code]....
How can I detect null value of sql parameter?In VB6 IsNull(), in VB.NET its return error
View 5 RepliesIn the following fragment I want to set vID2 to NULL (and not to 0) if mID2 is an empty string. How do I do this? There is apparently no OleDbType.Null
cn.Open()
strTemp = "INSERT INTO tbShips (vNew_b, vID, vID2) VALUES(?, ?, ?)"
MyCommand.Connection = cn
MyCommand.CommandText = strTemp
With MyCommand.Parameters
[Code]...