Asp.net - Error: Method 'First' Can Only Be Used As A Final Query Operation?
Mar 16, 2011
I have the following query:
Dim roommates = From p In dbroom.Residents _
Where p.room = queryStudent.First.r.id _
Where p.building = queryStudent.First.b.id _[co
de].....
But I still get the same error: The method 'First' can only be used as a final query operation. Consider using the method 'FirstOrDefault' in this instance instead.
Public Class Form1 Dim inc As Integer Dim MaxRows As Integer Dim con As New OleDb.OleDbConnection Dim dbProvider As String Dim dbSource As String Dim ds As New DataSet
I am new to Visual Basic 2008 and NET and am using the Visual Studio 2008 Express editions. I recently downloaded the ebook "Build a Program Now!" for VB and have been working through it without problem until te end of the penultimate chapter 8.
Part of the exercise includes the following code:
Private Sub tsbFilterByMake_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles tsbFilterByMake.Click Dim filteredByMake = From Listing In Me.CarTrackerDataSet.Listing _
[CODE].........
Whenever I attempt to execute this code, I get the error "The method or operation is not implemented" on the last line before the End Sub. This suprised me because when I typed in the f after the = sign, Intellisense offered me the single choice of the required filteredByMake, suggesting to me (in my probable naivety) that it recognised it as a syntactically corrrect choice. This is not down to an error on my part somewhere in attempting the exercise as I get the same result trying to run the Complete code solution that accompanies the book. I have successfully replaced this and a similar Sub with SQL queries on the datasets in question, why the above code does not work and what can be done to correct it.
this application for computing the gcd by using extended euclidean but it give me just the value for first iteration but i need the final values of x2 y2 a
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim x1 As Integer Dim x2 As Integer Dim y1 As Integer
I am programming an ordering site in VB.Net and ASP.Net.I start with the main ordering form and the idea is that the user will select a subject from the drop down list and then click a button to retrieve all modules associated with that subject in a second form (smaller than the main order form).I have created the second form (frm2) and added content to it.In the main form inside the method which represents the button being clicked, I have coded the following:
Dim frm As New frm2() frm.show()
I then get an error that show has not been declared and so I create a method stub for it.I run the program and when I click on the button I get the following error:'method or operation is not implemented.'This points to the following line in the 2nd form:
Sub show() Throw New NotImplementedException End Sub
what I need to put inside this method to make my second form load when the button is clicked?
I'm working in a windows app. with vb.net it is working very fine with me but after I make it as a setup file and install it it shows an error.I will explane the problem hereunder:the App. is for importing the data from xsl.file(user select it from file dialog)and store it in DB access file. It works pretty good when it is running in VS .. but after installation it is not.The error msg: "Operation must use an updateable query.""When JIT debugging is enabled, any unhandled exception.will be sent to the JIT debugger registered on the computer rather than be handled by this dialog box."
I have an error when I try update values from one data table into another.I am using microsoft access 2007.For the datatable in question I can Insert data into it no problem, but I get the following error when trying to update -
Operation must use an updateable query.I dont think it can be a permissions problem or a file access problem because I can execute an insert sql query on the same file.
I instal my program to other pc and now when i want to use it.it pop out "Operation must use updateable query".when i create it. it run perfectly.but when i instal to other pc.it pop up this error.what can i do to run my program perfectly on others pc...?
I have a windows form that gets data from a scale via the serial port. Since I need the operator to be able to cancel the process I do the get data process on a second thread. The data collection process gets multiple readings from the scale one at a time. The form has a label that needs to be updated with information specific to each reading.
I call the method to get the data from the scale with this code. Dim ad As New readALine(AddressOf thisScale.readALine) Dim ac As New AsyncCallback(AddressOf Me.GetDataCallback) Dim iar As IAsyncResult = ad.BeginInvoke("", ac, ad)
The delegate for the readALine method is defined in the UI code. Delegate Function readALine(ByVal toSend As String) As String
The GetDataCallback method: Private Sub GetDataCallback(ByVal ia As IAsyncResult) . . . lblInstructions.Text = _thisMeasure.dt.Rows(_currRow - 1).Item("cnt") & ":" lblInstructions.Refresh() . . . End Sub
I get the exception on the "lblInstructions.Text =" statement. I thought the GetDataCallback method was part of the UI thread so don't understand why I'm getting the exception. I know this could probably be rewritten using a BackgroundWorker and it's appropriate events but for now would like to understand why this isn't working as expected. The application was written originally in VS2003 and just recently upgraded to VS2008.
The code below works fine on my development PC, but when I deployed the app, it crashes.
Here is the lines of code that are relvant
Private TdsTypesList As List(Of TDS_Type) ... TdsTypesList = (From tt In db.TDS_Types Select tt).ToList
[Code].....
I have many queries that are using linq, and none of them throw any errors. The set of data is not very large either, less that 100 rows. I dont know if I have any other queries that do not have where statements in them that work.
Running .net 3.5 without sp1 on the client machine, although I am running sp1 on my development PC. looking for a solution that doesn't require sp1 to be installed.
Edit Code breaks on the second line when remote debugging.
I looked over [URL] and tried the following, with the same error.
TdsTypesList = tl.OfType(Of TDS_Type)().ToList
I finally found a dirty workaround. Instead of pulling all of columns from that table, I was able to re-write the query to omit 1 column. This returns an object of anonymous type, and I can use that object. I still would like to know what causes this though.
I am having a problem that I keep getting the following error when I try to run my program.I am trying to make a circle the size of the value of FrameSize.A first chance exception of type 'System.InvalidOperationException' occurred in System.Windows.Forms.dll
This is the details of the error:
System.InvalidOperationException was unhandled
Message=An error occurred creating the form. See Exception.InnerException for details. The error is: Cross-thread operation not valid: Control '' accessed from a thread other than the thread it was created on. Source=DreamCatcher[code]......
When Creating a query using the sear Criteria Builder . I keep getting the error : "The schema returned by the new query differs from the base query" what does that mean and how do i avoid this problem in future
Why does my the declaration of my string in the code result in the following error? Is there a workaround?
Code:
<script runat="server"> Protected Sub form1_Load(sender As Object, e As System.EventArgs) Dim x As String = "</script>"
[code]....
Error: Statement cannot appear within a method body. End of method assumed.
Note: The following page did not fix my issue and instead resulted in the string </script> being output in my page. ( VB.NET hates </script> tag in string literal )
The database: "ID (Primary key)" | "Title" 0 | "title1"
[code].....
OK, before adding values to database, we should check if a row exists with this values :)TO do this, creating a Stored Procedure is a best way to deal with the database fastly.So... The problem now is, at the runtime, Miss OleDB throw this error:Microsoft Jet database engine cannot find the input table or query 'IF
i should say hi experts :D . Help me with this pretty code :)
The database: "ID (Primary key)" | "Title" 0 | "title1"
[code].....
OK, before adding values to database, we should check if a row exists with this values :)TO do this, creating a Stored Procedure is a best way to deal with the database fastly.So... The problem now is, at the runtime, Miss OleDB throw this error:Microsoft Jet database engine cannot find the input table or query 'IF
I have 7 company Divisions that sit in an access database.I then use this list to populate two comboboxes in my windows form.However I get a syntax error in my SQL Query if the Division name is more than one word.For example in my access database I have two columns one is a status column and the other is a division column. If for example the Division is called 'Corporate' the status column is called 'Status Corporate' and the division column is called 'Corporate'.The SQL query works fine in this scenario.However if I have a Division that is more than one word, lets say 'Operations Division' I get an error in my SQL Query that says -
Quote: Syntax error (missing operator) in query expression 'Operations Division'.Here is my code
sqlNewTenderDetails = "SELECT " & Me.DivisionBox.SelectedValue & " From BidRefCodes Where " & "[Status " & Me.DivisionBox.SelectedValue & "='Active'" daNewTenderDetails = New OleDb.OleDbDataAdapter(sqlNewTenderDetails, NewTenderDetailsTableCon)[code]....
i have PDF forms creating .exe application using Crystal it is giving some times "Not enough memory for operation" error in production intermittently for below code. the error is not reproduced in TEST if i reset the same claim in next batch , it is creating PDF form without fail the server has enough memory the application is in .NET2003
I have installed vb.net 2010 express , but when I run It I get : "Error , the operation could not be completed".And I cannot do nothing with visual studio 2010.
I have developed an application in VB2008/MySql as database.I did serach record method but i need serach record using(Graterthan) >1000 and <5000(LessThan).Have a look at the normal search record code .
I've recently been trying to figure out a way to get parameterized queries to work and i think i'm almost there but seem to be getting an error when executing my query
I am using a DataReader to get data from a database. For some reason, I keep getting this error "Arithmetic operation resulted in an overflow." The error occurs on the line: courseID = (dr.Item("courseId"))
I made an icon for my program and tried to implement it.Funniest thing though, I get a message with the error icon saying the operation completed successfully.But the icon doesn't change, nor is it my icon drop down box when I click the arrow. Ergo, it didn't complete successfully....I am using ASP.NET 2.0 and have read some about this error but I don't see any fixes I can do, aside from what I've tried already.
I am running on the VB8 and expirienced an error during debugging after some changes in "My project" area. I have noticed (on two different machine) that after change for example Startup Form or Security Area, I am not able to debug program any longer. An error appears, telling me that:
The Operation Could not be completed.
After clicking OK (nothing else is available) and next try of debugging, another error message appear:
Visual Studio could not copy a support file to this location: "path". Please verify the path exists and is writeable. After that, I have to close Visual Basic and restart it. Than everything works fine...till next change of "My project"