开发实践教程1：试卷生成系统6.20 密码修改（FormPass）

Posted 2021-09-15 VB.Net

版权声明：本文为博主原创文章，转载请在显著位置标明本文出处以及作者网名，未经作者允许不得用于商业目的。

用户可以修改密码。

窗体设计如下：

 图1-30

具体代码如下：

Imports System.Data.SqlClient

Public Class FormPass
    Dim connection As SqlConnection


    Private Sub FormUser_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        connection = New SqlConnection(databaseConnString)
        connection.Open()

        txtName.Text = loginName
    End Sub

    Private Sub btnCancel_Click(sender As Object, e As EventArgs) Handles btnClose.Click
        Me.Close()
    End Sub

    Private Sub btnOk_Click(sender As Object, e As EventArgs) Handles btnOk.Click
        Dim passOld As String = txtPassOld.Text.Trim
        Dim passNew As String = txtPassNew.Text.Trim

        If passNew.Length < 6 Then
            MessageBox.Show("密码长度至少应为6位")
            Exit Sub
        End If

        Dim passOldMd5 As String = clsMd5.toMD5(passOld)
        Dim passNewMd5 As String = clsMd5.toMD5(passNew)

        Dim command As New SqlCommand()

        command.CommandText = "select 密码 from 用户表 where 编号=" & loginId
        command.Connection = connection

        Dim odReader As SqlDataReader
        Dim pass As String
        odReader = command.ExecuteReader(CommandBehavior.SingleResult)
        odReader.Read()
        pass = odReader.GetValue(0)
        odReader.Close()

        If pass <> passOldMd5 Then
            MessageBox.Show("原密码不正确，取消操作")
            Exit Sub
        End If

        command.CommandText = "update 用户表 set 密码='" & passNewMd5 & "' where 编号=" & loginId
        command.ExecuteNonQuery()

        MessageBox.Show("修改密码成功！")

    End Sub


    Private Sub FormPass_Closing(sender As Object, e As CancelEventArgs) Handles Me.Closing
        connection.Close()
    End Sub
End Class

由于.net平台下C#和vb.NET很相似，本文也可以为C#爱好者提供的参考。

学习更多vb.net知识，请参看 vb.net 教程 目录