Unable to cast object of type 'System.Int32' to type 'System.String'.

Question

           iNCEEB = .First.NCEEB '<-- Im getting the error in this line, iNCEEB is integer .First.NCEEB is short.

NCEEB Server Datatype property is smallint

where is that "to type 'System.String'." coming from?

I'm using vs2008 and mssql2008.

    Dim dbCEE As New CEE_LinqDataContext

    Dim iAppNo As Integer = 0

    Dim iNCEEB As Short? = Nothing
    Dim sNQI As String = ""
    Dim iRCEEB As Integer? = Nothing

Private Sub SearchCEE_Results()

        'Search Scores for CEE
        iAppNo = Integer.Parse(iAppNo)
        Dim CEESearchByAppNo = From CEEsearch In dbCEE.tblScanneds _
                                     Where CEEsearch.AppNo = iAppNo

        With CEESearchByAppNo

            If .Count > 0 Then
                iNCEEB = .First.NCEEB '<-- Im getting the error here
                sNQI = .First.NQI
                iRCEEB = .First.RCCEEB
                sRQI = .First.RCQI
                iICEEB = .First.ICEEB
                sIQI = .First.ITQI
                iTCEEB = .First.Total_CEEB
                sTQI = .First.TotQI
                sCEE_EXAMDATE = .First.ExamDate
                iCEE_Count = .Count
            Else

Answer 1

Hello WalangAlam,

           iNCEEB = .First.NCEEB '<-- Im getting the error in this line, iNCEEB is integer .First.NCEEB is short.

NCEEB Server Datatype property is smallint

where is that "to type 'System.String'." coming from?

I'm using vs2008 and mssql2008.

    Dim dbCEE As New CEE_LinqDataContext

    Dim iAppNo As Integer = 0

    Dim iNCEEB As Short? = Nothing
    Dim sNQI As String = ""
    Dim iRCEEB As Integer? = Nothing

Private Sub SearchCEE_Results()

        'Search Scores for CEE
        iAppNo = Integer.Parse(iAppNo)
        Dim CEESearchByAppNo = From CEEsearch In dbCEE.tblScanneds _
                                     Where CEEsearch.AppNo = iAppNo

        With CEESearchByAppNo

            If .Count > 0 Then
                iNCEEB = .First.NCEEB '<-- Im getting the error here
                sNQI = .First.NQI
                iRCEEB = .First.RCCEEB
                sRQI = .First.RCQI
                iICEEB = .First.ICEEB
                sIQI = .First.ITQI
                iTCEEB = .First.Total_CEEB
                sTQI = .First.TotQI
                sCEE_EXAMDATE = .First.ExamDate
                iCEE_Count = .Count
            Else

  I also seefrom the code thatthe variableDimiNCEEBand Short,
declaring Dim iNCEEB As Integer =0

Regards.

---

Carmelo La Monica

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Answer 2

Hello WalangAlam,

           iNCEEB = .First.NCEEB '<-- Im getting the error in this line, iNCEEB is integer .First.NCEEB is short.

NCEEB Server Datatype property is smallint

where is that "to type 'System.String'." coming from?

I'm using vs2008 and mssql2008.

    Dim dbCEE As New CEE_LinqDataContext

    Dim iAppNo As Integer = 0

    Dim iNCEEB As Short? = Nothing
    Dim sNQI As String = ""
    Dim iRCEEB As Integer? = Nothing

Private Sub SearchCEE_Results()

        'Search Scores for CEE
        iAppNo = Integer.Parse(iAppNo)
        Dim CEESearchByAppNo = From CEEsearch In dbCEE.tblScanneds _
                                     Where CEEsearch.AppNo = iAppNo

        With CEESearchByAppNo

            If .Count > 0 Then
                iNCEEB = .First.NCEEB '<-- Im getting the error here
                sNQI = .First.NQI
                iRCEEB = .First.RCCEEB
                sRQI = .First.RCQI
                iICEEB = .First.ICEEB
                sIQI = .First.ITQI
                iTCEEB = .First.Total_CEEB
                sTQI = .First.TotQI
                sCEE_EXAMDATE = .First.ExamDate
                iCEE_Count = .Count
            Else

  I also seefrom the code thatthe variableDimiNCEEBand Short,
declaring Dim iNCEEB As Integer =0

Regards.

---

Carmelo La Monica

• Blog
• WordPress
• Twitter

Answer 3

Hi,

In line iNCEEB = .First.NCEEB

Try:

if isDBNull(.First.NCEEB) then
   inCEEB = 0
else
   inCEEB = Convert.ToShort(.First.NCEEB)
end if

Maybe that .First.NCEEB has nothing value.

Regards

---

Agung Gugiaji My application developer journals

Answer 4

if isDBNull(.First.NCEEB) then <-- I'm getting same error here
   inCEEB = 0
else
   inCEEB = Convert.ToShort(.First.NCEEB)
end if

I also tried to show .First.NCEEB in a messagebox but same error.

like so

 With CEESearchByAppNo
            If .Count > 0 Then
                MessageBox.Show(.First.NCEEB)<--- same error here already.
                iNCEEB = .First.NCEEB

Answer 5

Walang you cannot "cast" those. Be aware the word cast is often misused. 

You can cast a class to its base class or cast it using the interface which is implemented. 

That is for Int32 and String not available. 

However you can convert an int to string

Dim x As String = CStr(0) 

if you want to put the decimal byte value of 0 in a string then it is

Dim x  = CStr(Asc(CStr(0)))

Also be aware that the use of int16 means less performance and not any memory gain, because the lowest integer which can be stored on a 32 bit system is Int32 and on a 64 bit system Int64.

The conversion between integers from DataBase to .Net and vice verse is done by the System.Data namespace automatically.

---

Success
Cor

Answer 6

There's nothing here to indicate that NCEEB is a Short data type. Hover over it when you break on that line, and it'll tell you the type.

(Ah, it's possible the data type has been Inferred since you are using LINQ, it seems).

---

Stephen J Whiteley

Answer 7

what I did was this.

Since it was working before, I didn't change my database structure and didn't change my code either went to LinqDataContext, reconnect to the database, delete the tblScanned and dropped same table using server explorer in the LinqDataContext. Now its working.

my code:

 Dim iAppNo As Integer = 0
    'Dim iNCEEB As Short? = Nothing
    Dim iNCEEB As Integer? = Nothing
    Dim sNQI As String = ""
    Dim iRCEEB As Integer? = Nothing
    Dim sRQI As String = ""
    Dim iICEEB As Integer? = Nothing
    Dim sIQI As String = ""
    Dim iTCEEB As Integer? = Nothing
    Dim sTQI As String = ""
    Dim iEptCEEB As Integer? = Nothing
    Dim sEptQI As String = ""
    Dim sEPT_Examdate As String = ""
    Dim sCEE_EXAMDATE As String = ""
    Dim iCEE_Count As Integer
    Dim iEPT_Count As Integer

  Private Sub SearchCEE_Results()

        'Search Scores for CEE
        iAppNo = Integer.Parse(iAppNo)
        Dim CEESearchByAppNo = From CEEsearch In dbCEE.tblScanneds _
                                     Where CEEsearch.AppNo = iAppNo

        With CEESearchByAppNo
            If .Count > 0 Then
                iNCEEB = .First.NCEEB
                sNQI = .First.NQI
                iRCEEB = .First.RCCEEB
                sRQI = .First.RCQI
                iICEEB = .First.ICEEB
                sIQI = .First.ITQI
                iTCEEB = .First.Total_CEEB
                sTQI = .First.TotQI
                sCEE_EXAMDATE = .First.ExamDate
                iCEE_Count = .Count
            Else
                iNCEEB = Nothing
                sNQI = ""
                iRCEEB = Nothing
                sRQI = ""
                iICEEB = Nothing
                sIQI = ""
                iTCEEB = Nothing
                sTQI = ""
                sCEE_EXAMDATE = DateTime.MinValue
                iCEE_Count = 0
            End If
        End With

    End Sub

Answer 8

Walang, 

Sorry, I did not see because of the thrash below this was code from used with a generated datacontext.

That has hidden designer code on board.

You can see it by doing in top of Solution Explorer "show all files".

Maybe you had an old generated designer part which contained wrong type names for the created properties and fields.

---

Success
Cor