异步委托数据绑定!

private void button1_Click(object sender, EventArgs e)
{
    GetLogDelegate getLogDel = new GetLogDelegate(GetLogs);
   
    getLogDel.BeginInvoke(new AsyncCallback(LogTableCallBack),  null);
}

public delegate DataTable GetLogDelegate();

/// <summary>
/// 从数据库中获取操作日志,该操作耗费时间较长,
/// 且返回数据量较大,日志记录可能超过万条。
/// </summary>
/// <returns></returns>
private DataTable GetLogs()
{
    string sql = "select * from ***";
    DataSet ds = new DataSet();

    using (OracleConnection cn = new OracleConnection(connectionString))
    {
        cn.Open();

        OracleCommand cmd = new OracleCommand(sql, cn);

        OracleDataAdapter adapter = new OracleDataAdapter(cmd);
        adapter.Fill(ds);
    }

    return ds.Tables[0];
}

/// <summary>
/// 绑定日志到ListBox控件。
/// </summary>
/// <param name="tag"></param>
private void LogTableCallBack(IAsyncResult tag)
{
    AsyncResult result = (AsyncResult)tag;
    GetLogDelegate del = (GetLogDelegate)result.AsyncDelegate;

    DataTable logTable = del.EndInvoke(tag);

    if (this.listBox1.InvokeRequired)
    {
        this.listBox1.Invoke(new MethodInvoker(delegate()
        {
            BindLog(logTable);
        }));
    }
    else
    {
        BindLog(logTable);
    }
}

private void BindLog(DataTable logTable)
{
    this.listBox1.DataSource = logTable;
}

posted on 2013-04-02 11:10  米高佐敦  阅读(197)  评论(0编辑  收藏  举报