在Visual Basic中创建更改密码窗体。如何更新SQL Server数据库？

Imports System.Data.SqlClient

Public Class ChangePasswordForm
    Dim connString As String = "Data Source=YourServerName;Initial Catalog=YourDatabaseName;User ID=YourUsername;Password=YourPassword"
    
    Private Sub ChangePasswordForm_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        ' 在窗体加载时，从数据库中获取当前密码并显示在标签上
        Dim conn As New SqlConnection(connString)
        Dim cmd As New SqlCommand("SELECT Password FROM Users WHERE Username = @Username", conn)
        cmd.Parameters.AddWithValue("@Username", "YourUsername") ' 替换为实际的用户名
        conn.Open()
        Dim password As String = cmd.ExecuteScalar().ToString()
        conn.Close()
        CurrentPasswordLabel.Text = password
    End Sub
    
    Private Sub ChangePasswordButton_Click(sender As Object, e As EventArgs) Handles ChangePasswordButton.Click
        ' 更新密码到数据库
        Dim conn As New SqlConnection(connString)
        Dim cmd As New SqlCommand("UPDATE Users SET Password = @NewPassword WHERE Username = @Username", conn)
        cmd.Parameters.AddWithValue("@NewPassword", NewPasswordTextBox.Text)
        cmd.Parameters.AddWithValue("@Username", "YourUsername") ' 替换为实际的用户名
        conn.Open()
        cmd.ExecuteNonQuery()
        conn.Close()
        MessageBox.Show("密码已成功更改！")
    End Sub
End Class