Question

我现在可以使用此代码将指纹直接保存到数据库...

   Dim fingerprintData As MemoryStream = New MemoryStream
    Template.Serialize(fingerprintData)
    fingerprintData.Position = 0
    Dim br As BinaryReader = New BinaryReader(fingerprintData)
    Dim bytes() As Byte = br.ReadBytes(CType(fingerprintData.Length, Int32))
    Dim cn As SqlConnection = New SqlConnection("Data Source=.\SQLEXPRESS;Initial Catalog=dataBEST;Integrated Security=True;Pooling=False")
    Dim cmd As SqlCommand = New SqlCommand("INSERT INTO fininger_table VALUES(@FIRSTNAME, @LASTNAME, @FINGERPRINT)", cn)
    cmd.Parameters.Add("FIRSTNAME", SqlDbType.VarChar).Value = CaptureForm.tboxFname.Text
    cmd.Parameters.Add("LASTNAME", SqlDbType.VarChar).Value = CaptureForm.tboxLname.Text
    cmd.Parameters.Add("FINGERPRINT", SqlDbType.Image).Value = bytes
    cn.Open()
    cmd.ExecuteNonQuery()
    cn.Close()

现在？如何检索该指纹并与用户匹配？顺便说一句，我的设备是DIGITAL PERSONA..tnx提前

Answer 1

应该相当简单。

1.) Simply fetch the data of your fingerprint using SqlDataReader
2.) Store the fetched value to a variable
3.) compare your bytes() variable with the fetched value.

如果您不熟悉如何使用datareader，请考虑此功能

 Function MSselectspecific(ByVal SQLComnd As String)
        Dim Sqlconn as New SQLConnection("your connection parameters")
        Dim sqlcommand As New SqlCommand(SQLComnd, Sqlconn)
        Dim reader As SqlDataReader
        Dim resulta As String = Nothing
        Dim x As Integer = 0
        Try
            Sqlconn.Open()
            reader = sqlcommand.ExecuteReader
            While reader.Read
                resulta = reader(0)
                x = x + 1

                Exit While
            End While
            Sqlconn.Close()
            If x > 0 Then
                Return resulta
            Else
                Return Nothing
            End If

        Catch ex As Exception
            Sqlconn.Close()
            MsgBox("Selectspecific Details Error    " & vbNewLine & ex.ToString)
            Return Nothing

        End Try
    End Function

并像这样使用它（以及保存用户指纹数据的变量） *注意：bytes（）是代码中包含指纹数据的部分，即（Dim bytes() As Byte = br.ReadBytes(CType(fingerprintData.Length, Int32))）

     if bytes() = val(MSSelectSpecific("select FINGERPRINT from fininger_table where FINGERPRINT = " & bytes() & ";")) then

     msgbox("Congrats! It's a match")
     End If

请注意，我使用val，因为您要比较两个数值。

如何匹配数据库中的指纹？

1 个答案: