Public Class Form1

    Private Function chaxun(a As String) As Object
        Try
            Dim ds As New SqlClient.SqlConnection
            Dim dm As New SqlClient.SqlCommand
            ds.ConnectionString = "Data Source=****;Initial Catalog=***;User ID=****;Password=******;"
            ds.Open()
            dm.Connection = ds

            dm.CommandText = "select top 1 itestlotno from WIPLOT where custeng = '" & a & "' order by custeng ,CreateTime  desc
"
            dm.ExecuteNonQuery()
            Dim r = dm.ExecuteScalar
            If r = Nothing Then
                dm.CommandText = "insert into WIPLOT(custeng,iTestLotNo,iTestProduct,CurrentStep,Status,CurrentQTY,createtime ) values ('" & a & "','100000000000',111,111111,1111,1111,'')"
                dm.ExecuteNonQuery()
                Return ""
            Else
                Return r
            End If

        Catch ex As Exception
            Dim ds As New SqlClient.SqlConnection
            Dim dm As New SqlClient.SqlCommand
            ds.ConnectionString = "Data Source=HOLLIEXU;Initial Catalog=FTMES;User ID=sa;Password=123456;"
            ds.Open()
            dm.Connection = ds
            dm.CommandText = "insert into WIPLOT(custeng,iTestLotNo,iTestProduct,CurrentStep,Status,CurrentQTY,createtime ) values ('" & a & "','100000000000',111,111111,1111,1111,'')"
            dm.ExecuteNonQuery()
            Return ""
        End Try

    End Function
    end class