vb.net中向数据库中定时添加数据?紧急求助!
我在程序一个按钮中中向数据库中添加了表,并且想在另一个按钮中向表中添加数据,
点击一下添加一次,现在的问题是只可以添加一次数据,再点击时提示表已经存在,
请问怎解决?麻烦各位,情况紧急!
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
strYear = System.DateTime.Now.Year.ToString()
strMonth = System.DateTime.Now.Month.ToString()
strDate = System.DateTime.Now.Day.ToString()
theName = "Table" + strYear + strMonth + strDate
'Dim sql As String = Nothing
'Dim MyInsert As String = Nothing
conn = New SqlConnection(ConnectionString)
If conn.State = ConnectionState.Open Then
conn.Close()
End If
conn.ConnectionString = ConnectionString
conn.Open()
sql = "CREATE TABLE " + theName + "" + "(myid NVARCHAR(50)," + "myname NVARCHAR(50) NOT Null,myaddress NVARCHAR(50))"
cmd = New SqlCommand(sql, conn)
Button2.Enabled = True
End Sub
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
conn = New SqlConnection(ConnectionString)
If conn.State = ConnectionState.Open Then
conn.Close()
End If
conn.ConnectionString = ConnectionString
conn.Open()
cmd = New SqlCommand(sql, conn)
Try
cmd.ExecuteNonQuery()
'添加记录
MyInsert = "INSERT INTO " + theName + "(myid,myname,myaddress)values(01,'王富力','dizhi')"
cmd = New SqlCommand(MyInsert, conn)
cmd.ExecuteNonQuery()
Catch ex As Exception
MessageBox.Show(ex.Message.ToString())
End Try
End Sub
[解决办法]
- VB.NET code
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click strYear = System.DateTime.Now.Year.ToString() strMonth = System.DateTime.Now.Month.ToString() strDate = System.DateTime.Now.Day.ToString() theName = "Table" + strYear + strMonth + strDate 'Dim sql As String = Nothing 'Dim MyInsert As String = Nothing conn = New SqlConnection(ConnectionString) If conn.State = ConnectionState.Open Then conn.Close() End If conn.ConnectionString = ConnectionString conn.Open() sql = "CREATE TABLE " + theName + "" + "(myid NVARCHAR(50)," + "myname NVARCHAR(50) NOT Null,myaddress NVARCHAR(50))" cmd = New SqlCommand(sql, conn) '这的SQL是建立表的语句 Button2.Enabled = True End Sub Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click conn = New SqlConnection(ConnectionString) If conn.State = ConnectionState.Open Then conn.Close() End If conn.ConnectionString = ConnectionString conn.Open() cmd = New SqlCommand(sql, conn) '这的SQL是建立表的语句 Try cmd.ExecuteNonQuery() '这是执行建立表的语句 '添加记录 MyInsert = "INSERT INTO " + theName + "(myid,myname,myaddress)values(01,'王富力','dizhi')" cmd = New SqlCommand(MyInsert, conn) '这的MyInsert是插入的语句 cmd.ExecuteNonQuery() '这是执行插入的语句 Catch ex As Exception MessageBox.Show(ex.Message.ToString()) End Try