实现类似Windows资源管理器的DataGrid
作者：孟宪会 出自：【孟宪会之精彩世界】 发布日期：2003年10月28日 8点28分12秒
在DataGrid中，我们可以实现类似Windows资源管理器的效果，即对列进行排序，该列颜色与其它列不同。下面就是实现的代码：
C#代码：
DataGridLikeWindowsExplorer.aspx
DataGridLikeWindowsExplorer
.gridtooltip {
BORDER-RIGHT: black 1px solid;
PADDING-RIGHT: 4px;
BORDER-TOP: black 1px solid;
PADDING-LEFT: 4px;
Z-INDEX: 200;
LEFT: 0px;
VISIBILITY: hidden;
PADDING-BOTTOM: 4px;
FONT: 9pt bold 宋体;
BORDER-LEFT: black 1px solid;
WIDTH: 150px;
COLOR: white;
PADDING-TOP: 4px;
BORDER-BOTTOM: black 1px solid;
POSITION: absolute;
TOP: 0px;
BACKGROUND-COLOR: #ff3316
}
Northwind职员表
DataGridLikeWindowsExplorer.aspx.cs
using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Data.SqlClient;
using System.Drawing;
using System.Web;
using System.Web.Caching;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
namespace aspxWebCS
{
///
/// DataGridLikeWindowsExplorer 的摘要说明。
///
public class DataGridLikeWindowsExplorer : System.Web.UI.Page
{
protected System.Web.UI.WebControls.DataGrid WinExplorerView_DataGrid;
protected System.Data.SqlClient.SqlDataAdapter m_sqlDataAdapter;
protected System.Data.SqlClient.SqlCommand m_sqlSelectCommand;
protected System.Data.SqlClient.SqlConnection m_sqlConnection;
protected System.Data.DataSet m_dsEmployees;
protected System.Data.DataView m_dvEmployees;
protected System.Collections.Hashtable colHeaderMap;
protected string m_strSortExpr;
protected string m_strSortOrder;
protected int m_iSortColumnIdx;
protected System.Web.UI.WebControls.PlaceHolder Tips_PlaceHolder;
protected string strConn = "Data Source=.;User Id=sa;Password=;Initial Catalog=Northwind;";
private void Page_Load(object sender, System.EventArgs e)
{
m_iSortColumnIdx = -1;
m_strSortExpr = "";
m_strSortOrder = "";
ProcessViewState();
PrepareColumnHeaderMap();
if (!IsPostBack)
{
BindGridToView();
}
}
private void PrepareColumnHeaderMap()
{
colHeaderMap = new Hashtable();
int idx = 0;
foreach (DataGridColumn col in WinExplorerView_DataGrid.Columns)
{
colHeaderMap[col.SortExpression] = idx++;
}
}
private void RetrieveData()
{
if (null == Cache["EmployeesDS"])
{
string tmp = "SELECT LastName, FirstName, Title, BirthDate, City FROM Employees";
m_sqlConnection = new SqlConnection(strConn);
m_sqlSelectCommand = new SqlCommand(tmp, m_sqlConnection);
m_sqlDataAdapter = new SqlDataAdapter(m_sqlSelectCommand);
m_dsEmployees = new DataSet("Employees");
m_sqlDataAdapter.Fill(m_dsEmployees);
Cache.Insert("EmployeesDS", m_dsEmployees, null, DateTime.Now.AddMinutes(1), Cache.NoSlidingExpiration);
}
else
{
m_dsEmployees = (DataSet)Cache["EmployeesDS"];
}
}
private void ProcessViewState()
{
if (null != ViewState["SortExpr"])
{
m_strSortExpr = ViewState["SortExpr"].ToString();
}
if (null != ViewState["SortOrder"])
{
m_strSortOrder = ViewState["SortOrder"].ToString();
}
}
private void BindGridToView()
{
string strSort = "";
if (0 != m_strSortExpr.Length)
{
strSort = m_strSortExpr;
if (0 != m_strSortOrder.Length)
{
strSort += (" " + m_strSortOrder);
}
}
RetrieveData();
m_dvEmployees = new DataView(m_dsEmployees.Tables[0], "", strSort, DataViewRowState.CurrentRows);
WinExplorerView_DataGrid.DataSource = m_dvEmployees;
WinExplorerView_DataGrid.DataBind();
}
private Color GetSortColumnColor()
{
if (null == this.m_strSortOrder ||
String.Empty == this.m_strSortOrder||
0 == this.m_strSortOrder.Length)
{
return Color.Gold;
}
if (m_strSortOrder.CompareTo("ASC") == 0)
{
return Color.Gold;
}
else
{
return Color.BlanchedAlmond;
}
}
private void OnPageIndexChange(object source, System.Web.UI.WebControls.DataGridPageChangedEventArgs e)
{
WinExplorerView_DataGrid.CurrentPageIndex = e.NewPageIndex;
BindGridToView();
}
private void OnSortView(object source, System.Web.UI.WebControls.DataGridSortCommandEventArgs e)
{
m_strSortExpr = e.SortExpression;
ViewState["SortExpr"] = m_strSortExpr;
if (0 == m_strSortOrder.Length)
{
m_strSortOrder = "ASC";
}
else if (m_strSortOrder.CompareTo("ASC") == 0)
{
m_strSortOrder = "DESC";
}
else
{
m_strSortOrder = "ASC";
}
ViewState["SortOrder"] = m_strSortOrder;
// 找到Click事件所在的列序号
m_iSortColumnIdx = Convert.ToInt32(this.colHeaderMap[m_strSortExpr]);
BindGridToView();
}
private void OnItemCreated(object sender, System.Web.UI.WebControls.DataGridItemEventArgs e)
{
if (e.Item.ItemType == ListItemType.Header)
{
int idx = 0;
foreach (TableCell cl in e.Item.Cells)
{
cl.Attributes.Add("onmouseover", "showheadertip(" + idx.ToString() + ");");
cl.Attributes.Add("onmouseout", "hideheadertip(" + idx.ToString() + ");");
idx++;
}
}
if (e.Item.ItemType == ListItemType.Item ||
e.Item.ItemType == ListItemType.AlternatingItem)
{
if (-1 != m_iSortColumnIdx)
{
e.Item.Cells[m_iSortColumnIdx].BackColor = GetSortColumnColor();
}
}
}
protected override void OnPreRender(EventArgs e)
{
///ToolTip文字
int nCount = this.WinExplorerView_DataGrid.Columns.Count;
for (int i = 0; i