創建表單時發生錯誤。有關詳細信息，請參閱Exception.InnerException。在視覺基礎2010

Question

我正在一個拼寫蜜蜂程序，它包含一個登錄系統，並花了數週試圖解決這個特定的錯誤，我在這裏是我的錯誤： 創建表單時發生錯誤。有關詳細信息，請參閱Exception.InnerException。錯誤是：The type initializer for 'Spelling_Bee_Programme.test' threw an exception。

下面是登錄系統我登錄代碼：

Imports System.Data.OleDb 'imports system O.L.E.D.B(Object Linking and Embedding database) functions 
Public Class formlogin ' startes class formlogin for the whole form 
Public Shared db_connection As New OleDbConnection 'declares db_connection as global variable and sets as new system O.L.E.D.B(Object Linking and Embedding database) connection 

Public Sub cmdlogin_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdlogin.Click ' when cmdlogin button pressed do following 
    Dim time_data As String 'declares time_data as datatype string 
    Dim file As String = "E:\login.txt" ' creates varible "file" and sets value as directory location 
    txtuser.Text = txtuser.Text.ToLower() 'This ensures that the username is converted to lowercase so database doesn't have a problem with random capitals being in a username 
    txtpass.Text = txtpass.Text.ToLower() 'This ensures that the password is converted to lowercase so database doesn't have a problem with random capitals being in a password 
    txtuser.Text = Trim(txtuser.Text) ' removes spaces at start and end of text in txtuser's text property 
    txtpass.Text = Trim(txtpass.Text) ' removes spaces at start and end of text in txt 
    formlogin.db_connection.ConnectionString = "Provider=Microsoft.jet.OLEDB.4.0; Data Source= H:\Spelling Bee Programme\Spelling Bee Programme\DBmainframe.mdb" 
    If txtpass.Text = "" Then ' clears textbox of passwordOr txtuser.text = "" ' clears textbox of usernameThen 'If username or password textbox is empty then do following 
     MsgBox("please enter a username or password") 'make a messagebox pop up and tell user that they have not entered anything in the textbox. 
     db_connection.Close() 'closes database because the database being open just incase it is accidently left open to ensure no problems. 'closes database because the database being open just incase it is accidently left open to ensure no problems. 
    ElseIf txtuser.Text = "root" And txtpass.Text = "password" Then 'if first condition is not meet check if username is equal to root and password is equal to password then do following which is not relient on database so that if problem with database. It is still possible to acess program as backup solution. 
     MsgBox("welcome root") ' makes a message box pop up and tell the user a welcome message saying the account they are logged in as. 
     Dim objwriter1 As New System.IO.StreamWriter(file, True) ' declares a the varible objwriter as system and pulls value of varible file which is directory of where to write data and true is write to file saying yes 
     time_data = DateTime.Now.ToLongDateString ' varible time_data's value equal to current time and date 
     DateTime.Now.ToString("hh:mm dddd, dd MMMM yyyy") ' this line formates the current time and date 
     objwriter1.WriteLine("root login @ " & time_data) 'appends that a recovery user logged in and time of login to file 
     objwriter1.Close() ' closes file writing 
     result.Show() ' show result from test form. 
     'closes database because the database being open just incase it is accidently left open to ensure no problems. 
    Else 'executes if condition not meet. 
     'Try ' this attempts the following 
     Dim SQLteacher As String = "SELECT * FROM teacher WHERE username = '" & txtuser.Text & "' AND teacher_password = '" & txtpass.Text & "'" ' This line states select everything from table(teacher) and where username is = what is in textbox username and password table is = to textbox password then compare for match but doesn't execute. 
     Dim sqlcomteacher As New System.Data.OleDb.OleDbCommand(SQLteacher, db_connection) 'setups connection settings for database 
     Dim SQLpupil As String = "SELECT * FROM pupil WHERE username = '" & txtuser.Text & "' AND pupil_password = '" & txtpass.Text & "'" ' This line states select everything from table(teacher) and where username is = what is in textbox username and password table is = to textbox password then compare for match but doesn't execute. 
     Dim sqlcompupil As New System.Data.OleDb.OleDbCommand(SQLpupil, db_connection) 'setups connection settings for database 
     db_connection.Open() ' opens database 
     Dim sqlreadteacher As System.Data.OleDb.OleDbDataReader = sqlcomteacher.ExecuteReader() 'executes database query 
     Dim sqlreadpupil As System.Data.OleDb.OleDbDataReader = sqlcompupil.ExecuteReader() 'executes database query 
     If sqlreadpupil.Read() Then 'if match for a teacher account sucessful then do following 
      MsgBox("Login Sucessful") 'make messagebox appear and say "Login SucessFul" 
      Dim objwriter As New System.IO.StreamWriter(file, True) 'declares the name of the file writer and uses variable file for location of writting of data and true to allow writting 
      time_data = DateTime.Now.ToLongDateString 'sets value of varible time_data = current time set on the computer 
      DateTime.Now.ToString("hh:mm dddd, dd MMMM yyyy") 'structures time and data by Hours, Minutes, Days, months and Year 
      objwriter.WriteLine("Teacher login @ " & time_data) 'writes on current line on file being created a "pupil login @ and then inputs time and data from variable time_data 
      objwriter.Close() ' closes file writing operation 
      My.Forms.test.Visible = True 
      Me.Hide() 'closes current form "Formlogin" 
      db_connection.Close() 'closes database because the database being open just incase it is accidently left open to ensure no problems. 

     ElseIf sqlreadteacher.Read() Then 'if match for a student account sucessful then do following. 
      MsgBox("Login Sucessful") 'make messagebox appear and say "Login SucessFul" 
      Dim objwriter As New System.IO.StreamWriter(file, True) 'declares the name of the file writer and uses variable file for location of writting of data and true to allow writting 
      time_data = DateTime.Now.ToLongDateString 'sets value of varible time_data = current time set on the computer 
      DateTime.Now.ToString("hh:mm dddd, dd MMMM yyyy") 'structures time and data by Hours, Minutes, Days, months and Year 
      objwriter.WriteLine("pupil login @ " & time_data) 'writes on current line on file being created a "pupil login @ and then inputs time and data from variable time_data 
      objwriter.Close() ' closes file writing operation 
      result.Show() 'opens form called "result" 
      Me.Hide() 'closes current form "Formlogin" 
      db_connection.Close() 'closes database because the database being open just incase it is accidently left open to ensure no problems. 
     Else : db_connection.Close() : MsgBox("Your username or password was incorrect.") 'closes database because the database being open just incase it is accidently left open to ensure no problems. 
     End If ' ends if statement 
     'Catch ex As Exception ' if error do following 
     'MessageBox.Show("Failed to connect to Database.. System Error Message: " & ex.Message, "Database Connection Error", MessageBoxButtons.OK, MessageBoxIcon.Error) 'makes messagebox popup and say "Failed to connect to database... System error message:" shows error message and code for user to give back to us. 
     db_connection.Close() 'closes database because the database being open just incase it is accidently left open to ensure no problems. 
     'End Try 'ends 'try statement 
    End If ' ends if statement 
End Sub ' ends subprocedure. 

Private Sub cmdcancel_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdcancel.Click 'when cancel button is clicked do following in subprocedure 
    db_connection.Close() 
    End 'ends whole program 
End Sub 'ends subprocedure 
End Class 'ends whole form procedure 

很想上如果可能的話如何解決這個錯誤的任何建議。

Answer 1

測試的代碼還沒有結束，但看看櫃面它是東西有：

進口System.Data.OleDb 公共類測試 昏暗vbscore作爲整數 昏暗FILE_NAME的String =「E： \ RESULTS.TXT」 昏暗SQL作爲字符串 昏暗噠作爲OleDb.OleDbDataAdapter 昏暗博士爲OleDb.OleDbDataReader 昏暗DS作爲新的數據集 昏暗CB作爲OleDb.OleDbCommandBuilder =無 昏暗我作爲整數 點心時間=查閱。 ToShortTimeString 公共S hared Definition（）As Label = {test.lbldefinition1，test.lbldefinition2，test.lbldefinition3，test.lbldefinition4，test.lbldefinition5，test.lbldefinition6，test.lbldefinition7，test.lbldefinition8，test.lbldefinition9，test.lbldefinition10}

Private Sub cmdsubmit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdsubmit.Click 
    Dim da As OleDb.OleDbDataAdapter 
    sql = "SELECT * FROM word" 
    da = New OleDbDataAdapter(sql, formlogin.db_connection) 
    Dim ds As New DataSet 
    formlogin.db_connection.ConnectionString = "Provider=Microsoft.jet.OLEDB.4.0; Data Source= E:\Spelling Bee Programme\Spelling Bee Programme\DBmainframe.mdb" 'uses varible from formlogin db_connection equal to software provider for database and location of database. 
    '------------------------------------------------------- fills dataset words below ---------------------------------------------- 
    Dim dataset As DataTable = New DataTable("word") 

    formlogin.db_connection.Open() 'uses variable from formlogin db_connection to open database 
    da.Fill(ds, "words") 
    formlogin.db_connection.Close() 
    formlogin.db_connection.Open() 'uses variable from formlogin db_connection to open database 

    vbscore = 0 ' resets value to ensure that you can not get a score over 20 which is the maximum value if you got every question right. 
    Dim wordsarray() As TextBox = {txt1, txt2, txt3, txt4, txt5, txt6, txt7, txt8, txt9, txt10} 
    Dim reviewscore() As String = {lblscorereview1.Text, lblscorereview2.Text, lblscorereview3.Text, lblscorereview4.Text, lblscorereview5.Text, lblscorereview6.Text, lblscorereview7.Text, lblscorereview8.Text, lblscorereview9.Text, lblscorereview10.Text} 
    Dim i As Integer 
    For i = 0 To 9 
     wordsarray(i).Text = wordsarray(i).Text.ToUpper() 
     i = i + 1 
    Next 
    i = 0 
    For i = 0 To 9 
     If wordsarray(i).Text = "" Then 
      MsgBox("Please Fill in all the TextBoxes") 
      wordsarray(i).Focus() 
      formlogin.db_connection.Close() 
      Exit Sub 
     ElseIf wordsarray(i).Text = ds.Tables("words").Rows(i).Item(1) Then 
      vbscore = vbscore + 2 'adds 2 to varible "vbscore" if correct 
      reviewscore(i) = vbscore 
      lblresult.Text = Val(lblresult.Text) + Val(i) 
      formlogin.db_connection.Close() 
     End If 
    Next 
    Dim objwriter As New System.IO.StreamWriter(FILE_NAME, True) 
    Dim tbscore As DataTable = New DataTable("score") 
    Dim cmdInsert As New OleDbCommandBuilder(da) 
    sql = "SELECT * FROM result" 
    da = New OleDbDataAdapter(sql, formlogin.db_connection) 
    formlogin.db_connection.Open() 
    da.Fill(ds, "score") 
    ds.Tables("score").Rows(0).Item(0) = formlogin.txtuser.Text 
    ds.Tables("score").Rows(1).Item(1) = tbscore 
    da.Update(ds, "score") 
    formlogin.db_connection.Close() 
    time = DateTime.Now.ToLongDateString 
    DateTime.Now.ToString("hh:mm:ss dddd, dd MMMM yyyy") 
    objwriter.WriteLine(formlogin.txtuser.Text & " score = " & vbscore & " attempted test at " & time) 
    objwriter.WriteLine() 
    objwriter.Close() 
    formlogin.db_connection.Close() 
    MsgBox("Thank you for taking part in the test you're score was " & vbscore) ' shows partisapent a thank you message and what score they got in the test. 
    Me.Close() 
    formlogin.Show() 
End Sub 
Private Function Mark(ByVal InputtedWord As String, ByVal DBWord As String) As String 
    Dim i As Integer 
    Dim wrongletters As Integer 
    Dim InputCharacter As Char 
    Dim DbChar As Char 
    Dim inputcounter As Integer 
    Dim dbcounter As Integer 
    Dim inputtextlength As Integer 
    Dim dbtextlength As Integer 
    Dim maxtextlength As Integer 
    InputtedWord = InputtedWord.ToUpper 
    inputtextlength = InputtedWord.Length 
    DBWord = DBWord.ToUpper 
    dbtextlength = DBWord.Length 
    If inputtextlength >= dbtextlength Then 
     maxtextlength = inputtextlength 
    Else 
     maxtextlength = dbtextlength 
    End If 
    inputcounter = 0 
    dbcounter = 0 
    For i = 0 To maxtextlength - 1 
     InputCharacter = InputtedWord(inputcounter) 
     DbChar = DBWord(dbcounter) 
     If InputCharacter <> DbChar Then 
      wrongletters = wrongletters + 1 
     End If 
     If inputcounter <> inputtextlength - 1 Then 
      inputcounter = inputcounter + 1 
     End If 
     If dbcounter <> dbtextlength - 1 Then 
      dbcounter = dbcounter + 1 
     End If 

    Next i 

    If wrongletters >= 2 Then 
     Mark = "0" 
    ElseIf wrongletters = 1 Then 
     Mark = "1" 
    Else : Mark = "2" 
    End If 
End Function 


Private Sub test_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load 
End Sub 

Private Sub ComboBox1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cbWeek.SelectedIndexChanged 
    If cbWeek.SelectedItem = "" Then 
     MsgBox("Please select a week and then press load to start the test") 
    End If 
End Sub 

Private Sub btnload_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnload.Click 
    For Me.i = 0 To 9 
     Definition(i).Text = ds.Tables("word").Rows(i).Item(0) 
    Next 
End Sub 

末級