在訪問數據庫中使用vb中的Adox創建表

Question

我在Visual Basic 2012中使用Windows窗體應用程序來使用.ADOX創建新的Microsoft Access數據庫。我可以創建數據庫，但不能在數據庫中創建表。

我的代碼是：

Imports ADOX 
Imports System.Data.OleDb 
Public Class Form1 
Dim mycommand As OleDbCommand 
Dim myconnection As OleDbConnection 
Dim myReader As OleDbDataReader 
Dim str As String 
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click 
    Dim cat As New Catalog() 
    Dim tablename As String = "Users" 
    cat.Create("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=F:\important\DDL.mdb;Jet OLEDB:Engine Type=5") 
    cat = Nothing 
    myconnection = New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=F:\important\DDL.mdb ") 
    myconnection.Open() 
    str = "CREATE TABLE [ " & tablename & "] ([Username] varchar(50)), ([Password] varchar(50)), ([E-mail] varchar(75))" 
    mycommand = New OleDb.OleDbCommand(str, myconnection) 
    mycommand.ExecuteNonQuery() 
    MsgBox("Database created") 
End Sub 
End Class 

的錯誤是得到的是：

An unhandled exception of type 'System.Data.OleDb.OleDbException' occurred in System.Data.dll 

Additional information: Syntax error in CREATE TABLE statement. 

任何幫助表示讚賞。

編輯： 下面的代碼獲取第一個錯誤，但我現在得到一個字段定義錯誤，我知道代碼應該工作，因爲它與添加一個數字字段，可能是因爲訪問字段類型是短文本和長文本，但我試過的任何東西似乎都不起作用。

Imports ADOX 
Imports System.Data.OleDb 
Public Class Form1 
Dim mycommand As OleDbCommand 
Dim myconnection As OleDbConnection 
Dim myReader As OleDbDataReader 
Dim str As String 
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click 
    Dim cat As New Catalog() 
    cat.Create("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=F:\important\DDL.mdb;Jet OLEDB:Engine Type=5") 
    cat = Nothing 
    myconnection = New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=F:\important\DDL.mdb ") 
    myconnection.Open() 
    str = "CREATE TABLE [Users] (Username Varchar(50), Password Varchar(50), E-mail Varchar(50))" 

    mycommand = New OleDb.OleDbCommand(str, myconnection) 
    mycommand.ExecuteNonQuery() 
    MsgBox("Database created") 
End Sub 
End Class 

Answer 1

看起來你有太多的parenthesizes，但我認爲實際的錯誤是從你在查詢擁有領先的空間來：

     V 
str = "CREATE TABLE [ " & tablename & "] 

嘗試將其更改爲：

str = "CREATE TABLE [" & tablename & "] ([Username] varchar(50), [Password] varchar(50), [E-mail] varchar(75))" 

請確保您處理您的物品，最好在使用區塊中：

示例：

Using cn As New OleDb.OleDbConnection(mdb) 
    cn.Open() 
    Using cmd As New OleDb.OleDbCommand(str, cn) 
    cmd.ExecuteNonQuery() 
    End Using 
End Using