// 1、定义几个所需的公有成员:
int pageSize = 0; //每页显示行数
int nMax = 0; //总记录数
int pageCount = 0; //页数=总记录数/每页显示行数
int pageCurrent = 0; //当前页号
int nCurrent = 0; //当前记录行
DataSet ds = new DataSet();
DataTable dtInfo = new DataTable();
//2、在窗体载入事件中,从数据源读取记录到DataTable中:
string strConn = "SERVER=127.0.0.1;DATABASE=NORTHWIND;UID=SA;PWD=ULTRATEL"; //数据库连接字符串
SqlConnection conn = new SqlConnection(strConn);
conn.Open();
string strSql = "SELECT * FROM CUSTOMERS";
SqlDataAdapter sda = new SqlDataAdapter(strSql,conn);
sda.Fill(ds,"ds");
conn.Close();
dtInfo = ds.Tables[0];
InitDataSet();
//3、用当前页面数据填充DataGridView
private void InitDataSet()
{
pageSize = 20; //设置页面行数
nMax = dtInfo.Rows.Count;
pageCount=(nMax/pageSize); //计算出总页数
if ((nMax % pageSize) > 0) pageCount++;
pageCurrent = 1; //当前页数从1开始
nCurrent = 0; //当前记录数从0开始
LoadData();
}
private void LoadData()
{
int nStartPos = 0; //当前页面开始记录行
int nEndPos = 0; //当前页面结束记录行
DataTable dtTemp = dtInfo.Clone(); //克隆DataTable结构框架
if (pageCurrent == pageCount)
{
nEndPos = nMax;
}
else
{
nEndPos = pageSize * pageCurrent;
}
nStartPos = nCurrent;
lblPageCount.Text = pageCount.ToString();
txtCurrentPage.Text = Convert.ToString(pageCurrent);
//从元数据源复制记录行
for (int i = nStartPos; i < nEndPos; i++)
{
dtTemp.ImportRow(dtInfo.Rows[i]);
nCurrent++;
}
bdsInfo.DataSource = dtTemp;
bdnInfo.BindingSource = bdsInfo;
dgvInfo.DataSource = bdsInfo;
}
// 4、菜单响应事件:
private void bdnInfo_ItemClicked(object sender, ToolStripItemClickedEventArgs e)
{
if (e.ClickedItem.Text == "关闭")
{
this.Close();
}
if (e.ClickedItem.Text == "上一页")
{
pageCurrent--;
if (pageCurrent <= 0)
{
MessageBox.Show("已经是第一页,请点击“下一页”查看!");
return;
}
else
{
nCurrent = pageSize * (pageCurrent - 1);
}
LoadData();
}
if (e.ClickedItem.Text == "下一页")
{
pageCurrent++;
if (pageCurrent > pageCount)
{
MessageBox.Show("已经是最后一页,请点击“上一页”查看!");
return;
}
else
{
nCurrent=pageSize*(pageCurrent-1);
}
LoadData();
}
} |