sdk/samples/all in on code/Visual Studio 2008/CSASPNETDataListImageGallery/Default.aspx.cs

   1 /****************************** Module Header ******************************\
   2 Module Name:  Default.aspx
   3 Project:      CSASPNETDataListImageGallery
   4 Copyright (c) Microsoft Corporation.
   5
   6 This module is used to show how to do a simple image gallery with a thumbnail
   7 navigation bar using DataList. User can select a thumbnail image from DataList
   8 to view the bigger one in main image. This can be implemented in some personal
   9 space site, online shopping site and etc.
  10
  11
  12 This source is subject to the Microsoft Public License.
  13 See http://www.microsoft.com/opensource/licenses.mspx#Ms-PL.
  14 All other rights reserved.
  15
  16 THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND,
  17 EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED
  18 WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR PURPOSE.
  19 \***************************************************************************/
  20
  21 using System;
  22 using System.Web.UI.WebControls;
  23 using System.IO;
  24 using System.Data;
  25
  26 namespace CSASPNETDataListImageGallery
  27 {
  28     public partial class _Default : System.Web.UI.Page
  29     {
  30         // Set page size.
  31         int _pageSize = 5;
  32
  33         // Property for current page index.
  34         public int Page_Index
  35         {
  36             get { return (int)ViewState["_Page_Index"]; }
  37             set { ViewState["_Page_Index"] = value; }
  38         }
  39
  40         // Property for total page count.
  41         public int Page_Count
  42         {
  43             get { return (int)ViewState["_Page_Count"]; }
  44             set { ViewState["_Page_Count"] = value; }
  45         }
  46
  47         protected void Page_Load(object sender, EventArgs e)
  48         {
  49             if (!Page.IsPostBack)
  50             {
  51                 // Initial page index.
  52                 Page_Index = 0;
  53
  54                 // Set page count.
  55                 if ((ImageCount() % _pageSize) == 0)
  56                 {
  57                     Page_Count = ImageCount() / _pageSize;
  58                     if (Page_Count == 0)
  59                     {
  60                         lbnFirstPage.Enabled = false;
  61                         lbnPrevPage.Enabled = false;
  62                         lbnNextPage.Enabled = false;
  63                         lbnLastPage.Enabled = false;
  64                     }
  65                 }
  66                 else
  67                 {
  68                     Page_Count = (ImageCount() / _pageSize + 1);
  69                 }
  70
  71                 // Bind DataList.
  72                 DataList1.DataSource = BindGrid();
  73                 DataList1.DataBind();
  74
  75                 // Disable two buttons for the initial page.
  76                 lbnFirstPage.Enabled = false;
  77                 lbnPrevPage.Enabled = false;
  78             }
  79         }
  80
  81         // Return the data source for DataList.
  82         protected DataTable BindGrid()
  83         {
  84             // Get all image paths.
  85             DirectoryInfo di = new DirectoryInfo(Server.MapPath("/Image/"));
  86             FileInfo[] fi = di.GetFiles();
  87
  88             // Save all paths to the DataTable as the data source.
  89             DataTable dt = new DataTable();
  90             DataColumn dc = new DataColumn("Url", typeof(System.String));
  91             dt.Columns.Add(dc);
  92             int lastindex = 0;
  93             if (Page_Count == 0 || Page_Index == Page_Count - 1)
  94             {
  95                 lastindex = ImageCount();
  96             }
  97             else
  98             {
  99                 lastindex = Page_Index * _pageSize + 5;
 100             }
 101             for (int i = Page_Index * _pageSize; i < lastindex; i++)
 102             {
 103                 DataRow dro = dt.NewRow();
 104                 dro[0] = fi[i].Name;
 105                 dt.Rows.Add(dro);
 106             }
 107             return dt;
 108         }
 109
 110         // Return total number of images.
 111         protected int ImageCount()
 112         {
 113             DirectoryInfo di = new DirectoryInfo(Server.MapPath("/Image/"));
 114             FileInfo[] fi = di.GetFiles();
 115             return fi.GetLength(0);
 116         }
 117
 118         // Handle the navigation button event.
 119         public void Page_OnClick(Object sender, CommandEventArgs e)
 120         {
 121             if (e.CommandName.Equals("first"))
 122             {
 123                 Page_Index = 0;
 124                 lbnFirstPage.Enabled = false;
 125                 lbnPrevPage.Enabled = false;
 126                 lbnNextPage.Enabled = true;
 127                 lbnLastPage.Enabled = true;
 128             }
 129             else if (e.CommandName.Equals("prev"))
 130             {
 131                 Page_Index -= 1;
 132                 if (Page_Index == 0)
 133                 {
 134                     lbnFirstPage.Enabled = false;
 135                     lbnPrevPage.Enabled = false;
 136                     lbnNextPage.Enabled = true;
 137                     lbnLastPage.Enabled = true;
 138                 }
 139                 else
 140                 {
 141                     lbnFirstPage.Enabled = true;
 142                     lbnPrevPage.Enabled = true;
 143                     lbnNextPage.Enabled = true;
 144                     lbnLastPage.Enabled = true;
 145                 }
 146             }
 147             else if (e.CommandName.Equals("next"))
 148             {
 149                 Page_Index += 1;
 150                 if (Page_Index == Page_Count - 1)
 151                 {
 152                     lbnFirstPage.Enabled = true;
 153                     lbnPrevPage.Enabled = true;
 154                     lbnNextPage.Enabled = false;
 155                     lbnLastPage.Enabled = false;
 156                 }
 157                 else
 158                 {
 159                     lbnFirstPage.Enabled = true;
 160                     lbnPrevPage.Enabled = true;
 161                     lbnNextPage.Enabled = true;
 162                     lbnLastPage.Enabled = true;
 163                 }
 164             }
 165             else if (e.CommandName.Equals("last"))
 166             {
 167                 Page_Index = Page_Count - 1;
 168                 lbnFirstPage.Enabled = true;
 169                 lbnPrevPage.Enabled = true;
 170                 lbnNextPage.Enabled = false;
 171                 lbnLastPage.Enabled = false;
 172             }
 173
 174             DataList1.SelectedIndex = 0;
 175             DataList1.DataSource = BindGrid();
 176             DataList1.DataBind();
 177             Image1.ImageUrl
 178                 = ((Image)DataList1.Items[0].FindControl("imgBtn")).ImageUrl;
 179         }
 180
 181         // Handle the thumbnail image selecting event.
 182         protected void imgBtn_Click(object sender, EventArgs e)
 183         {
 184             ImageButton ib = (ImageButton)sender;
 185             Image1.ImageUrl = ib.ImageUrl;
 186             DataList1.SelectedIndex = Convert.ToInt32(ib.CommandArgument);
 187         }
 188     }
 189 }