news.aspx.cs

wrox c#高级编程

using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
using Wrox.WebModules.Accounts.Business;

namespace Wrox.WebModules.NewsManager.Web
{
	/// <summary>
	/// Summary description for news.
	/// </summary>
	public class News : Wrox.ThePhile.Web.PhilePage
	{
		protected System.Web.UI.WebControls.DropDownList CatDropDown;
		protected System.Web.UI.WebControls.TextBox EditTitle;
		protected System.Web.UI.WebControls.TextBox EditBody;
		protected System.Web.UI.WebControls.TextBox EditReleaseDate;
		protected System.Web.UI.WebControls.TextBox EditExpireDate;
		protected System.Web.UI.WebControls.CheckBox EditApproved;
		protected System.Web.UI.WebControls.DataGrid NewsGrid;
		protected System.Web.UI.WebControls.Table TableNews;
		protected System.Web.UI.WebControls.LinkButton AddNew;
		protected System.Web.UI.WebControls.LinkButton CancelAddNew;
		protected System.Web.UI.WebControls.HyperLink AddCancel;
		protected System.Web.UI.WebControls.Table TableAddNews;
		protected System.Web.UI.WebControls.TextBox NewTitle;
		protected System.Web.UI.WebControls.TextBox NewBody;
		protected System.Web.UI.WebControls.TextBox NewReleaseDate;
		protected System.Web.UI.WebControls.TextBox NewExpireDate;
		protected System.Web.UI.WebControls.CheckBox NewApproved;
		protected System.Web.UI.WebControls.Button Create;
		protected System.Web.UI.WebControls.TableRow AddNewControlsRow;
		protected System.Web.UI.WebControls.TableRow CreateNewRow;
		protected System.Web.UI.WebControls.TableCell AddNewResultCell;
		protected System.Web.UI.WebControls.Label AddNewError;
		protected System.Web.UI.WebControls.RadioButton ShowApproved;
		protected System.Web.UI.WebControls.RadioButton ShowPending;
		protected System.Web.UI.WebControls.RadioButton ShowPast;
		protected System.Web.UI.WebControls.RadioButton ShowCurrent;
		protected System.Web.UI.WebControls.RadioButton ShowFuture;
		protected System.Web.UI.WebControls.Label NewsPreview;

		protected void Page_Load(object sender, EventArgs e)
		{
			// check if the current user is allowed to administer the news
			if (!Context.User.Identity.IsAuthenticated || 
				!((PhilePrincipal)Context.User).HasPermission((int)NewsManagerPermissions.AdministerNews))
			{
				// if not, redirect to the Login page
				Response.Redirect("/ThePhile/Modules/Users/Login.aspx?ShowError=true", true);
			}

			// get the CategoryID from the QueryString
			string categoryID = Request.Params["CategoryID"];
			NewsGrid.Attributes["CategoryID"] = categoryID;
			
			if (!Page.IsPostBack)
			{
				// load all the available lists in the DropDown control
				DataView myDV = Business.Category.GetCategories().Tables[0].DefaultView;
				CatDropDown.DataSource = myDV;
				CatDropDown.DataBind();

				if (categoryID!=null)
				{
					// select the DropDown element according to the CategoryID
					CatDropDown.SelectedIndex = CatDropDown.Items.IndexOf(
						CatDropDown.Items.FindByValue(categoryID));
				}
				
				// (re)bind the page's controls
				BindGrid();
			}
		}

		protected void BindGrid() 
		{
			int categoryID;

			// get the CategoryID value from the Grid's attributes
			if ( NewsGrid.Attributes["CategoryID"] != null )
				categoryID = int.Parse(NewsGrid.Attributes["CategoryID"]);
			else
				categoryID = int.Parse(CatDropDown.SelectedItem.Value);

			// get all the news of this category
			DataView myDV = new Business.Category(categoryID).GetNews(false).Tables[0].DefaultView;

			// sort the records according to the SortExpression value in the Grid's attributes
			if ( NewsGrid.Attributes["SortExpression"]!="" )
				myDV.Sort = NewsGrid.Attributes["SortExpression"];
			
			// show only the approved/pending news, as specified in the options
			if (ShowApproved.Checked)
				myDV.RowFilter = "Approved = 1";
			else if (ShowPending.Checked)
				myDV.RowFilter = "Approved = 0";
			else
				myDV.RowFilter = "1 = 1";
			// show only the past/current/future news, if specified in the options
			if (ShowPast.Checked)
				myDV.RowFilter += " AND ExpireDate < '" + DateTime.Today + "'";
			else if (ShowCurrent.Checked)
				myDV.RowFilter += " AND ReleaseDate <= '" + DateTime.Today + "' AND ExpireDate >= '" + DateTime.Today + "'";
			else if (ShowFuture.Checked)
				myDV.RowFilter += " AND ReleaseDate > '" + DateTime.Today + "'";

			NewsGrid.DataSource = myDV;
			NewsGrid.DataBind();
			
		}

		protected void CatDropDown_IndexChanged(object sender, EventArgs e)
		{
			// reload the page to show the news for the selected category
			// This will also hide the controls to add a news if they were visible
			Response.Redirect("News.aspx?CategoryID=" + CatDropDown.SelectedItem.Value);
		}
		
		protected void ShowNews_CheckedChanged(object sender, EventArgs e)
		{
			UnselectGridItem();
			// filter the news for the grid
			BindGrid();
		}

		protected void NewsGrid_PageChanged(Object sender, DataGridPageChangedEventArgs e)
		{
			// the DataGrid page is changed, so hide the controls for adding a new record
			// if they were visible
			UnselectGridItem();
			AddNewError.Visible = false;
			ShowAddNewControls(false);
			// change the current page
			NewsGrid.CurrentPageIndex = e.NewPageIndex;
			BindGrid();
		}
		
		protected void NewsGrid_Sort(Object sender, DataGridSortCommandEventArgs e) 
		{
			UnselectGridItem();
			AddNewError.Visible = false;
			ShowAddNewControls(false);
			NewsGrid.EditItemIndex = -1;
			// set the SortExpression attribute that will be used to actually sort
			// the data in the BindGrid method
			NewsGrid.Attributes["SortExpression"] = e.SortExpression.ToString();
			BindGrid();
		}

		protected void NewsGrid_Edit(object sender, DataGridCommandEventArgs e)
		{
			UnselectGridItem();
			AddNewError.Visible = false;
			ShowAddNewControls(false);
			// start the editing for this item
			NewsGrid.EditItemIndex = (int)e.Item.ItemIndex;
			BindGrid();
		}

		protected void NewsGrid_CancelEdit(object sender, DataGridCommandEventArgs e)
		{
			NewsGrid.EditItemIndex = -1;
			BindGrid();
		}

		protected void NewsGrid_Update(object sender, DataGridCommandEventArgs e)
		{
			if (Page.IsValid)
			{
				int newsID = (int)NewsGrid.DataKeys[e.Item.ItemIndex];
				// get the new values for the textboxes
				string title = ((TextBox)e.Item.FindControl("EditTitle")).Text;
				string body = ((TextBox)e.Item.FindControl("EditBody")).Text;
				bool approved = ((CheckBox)e.Item.FindControl("EditApproved")).Checked;
				
				// set predefined release/expire dates, in case they are not specified
				DateTime releaseDate = DateTime.Today;
				DateTime expireDate = new DateTime(3000,1,1);
				
				// get a reference to the textboxes with the dates
				TextBox releaseDateTB = (TextBox)e.Item.FindControl("EditReleaseDate");
				TextBox expireDateTB = (TextBox)e.Item.FindControl("EditExpireDate");
						
				// if the release date is specified, take that, if not keep the predefined
				if (releaseDateTB.Text.Trim().Length > 0)
					releaseDate = DateTime.Parse(releaseDateTB.Text);
				if (expireDateTB.Text.Trim().Length > 0)
					expireDate = DateTime.Parse(expireDateTB.Text);
				
				// update the news
				Business.News news = new Business.News(newsID);
				news.Title = title;
				news.Body = body;
				news.ReleaseDate = releaseDate;
				news.ExpireDate = expireDate;
				news.Approved = approved;
				news.Update();
				
				NewsGrid.EditItemIndex = -1;	
				BindGrid();
			}
		}

		protected void NewsGrid_Delete(object sender, DataGridCommandEventArgs e)
		{
			UnselectGridItem();
			AddNewError.Visible = false;
			ShowAddNewControls(false);
			NewsGrid.EditItemIndex = -1;
			// delete this news
			Business.News news = new Business.News((int)NewsGrid.DataKeys[e.Item.ItemIndex]);
			news.Delete();
			BindGrid();
		}

		protected void NewsGrid_SelectionChanged(object sender, EventArgs e)
		{	
			ShowAddNewControls(false);

			// get the ID of the selected row
			int newsID = int.Parse(NewsGrid.DataKeys[NewsGrid.SelectedIndex].ToString());
			// show the Body text in the Preview label
			NewsPreview.Text = new Business.News(newsID).Body;
			NewsPreview.Visible = true;
			
			NewsGrid.EditItemIndex = -1;
			BindGrid();
		}

		protected void AddNew_Click(object sender, EventArgs e)
		{
			if (Page.IsValid)
			{
				int categoryID = int.Parse(CatDropDown.SelectedItem.Value);
				string title = NewTitle.Text;
				string body = NewBody.Text;
				bool approved = NewApproved.Checked;

				// set predefined release/expire dates, in case they are not specified
				DateTime releaseDate = DateTime.Today;
				DateTime expireDate = new DateTime(3000,1,1);
									
				// if the dates are supplied, take them, otherwise keep the predefined
				if (NewReleaseDate.Text.Trim().Length > 0)
					releaseDate = DateTime.Parse(NewReleaseDate.Text);
				if (NewExpireDate.Text.Trim().Length > 0)
					expireDate = DateTime.Parse(NewExpireDate.Text);
									
				// add the news
				Business.Category category = new Business.Category(categoryID);
				SiteIdentity currUser = (SiteIdentity)Context.User.Identity;
				if (category.AddNews(title, body, releaseDate, expireDate, approved, currUser.UserID).ID < 0)
				{
					// if the call to the Add method returned -1, it means that this news
					// was already present, so show the label that tells this
					AddNewError.Visible = true;	
				}
				
				// hide the controls for adding a news
				ShowAddNewControls(false);
				BindGrid();
			}
		}
		
		protected void CancelAddNew_Click(object sender, EventArgs e)
		{
			ShowAddNewControls(false);
		}

		protected void Create_Click(object sender, EventArgs e)
		{
			// show the controls for adding a new subscriber and unselect the selected item
			UnselectGridItem();
			AddNewError.Visible = false;
			ShowAddNewControls(true);
			NewsGrid.EditItemIndex = -1;
			BindGrid();
		}
		
		protected void UnselectGridItem()
		{
			// hide the Preview control and unselect the selected row
			NewsGrid.SelectedIndex = -1;
			NewsPreview.Text = "";
			NewsPreview.Visible = false;
		}
		
		protected void ShowAddNewControls(bool ShowControls)
		{
			// show or hide the controls for adding a new subscriber
			NewTitle.Text = "";
			NewBody.Text = "";
			NewReleaseDate.Text = "";
			NewExpireDate.Text = "";
			NewApproved.Checked = true;

			CreateNewRow.Visible = !ShowControls;
			AddNewResultCell.Visible = !ShowControls;
			AddNewControlsRow.Visible = ShowControls;
		}

		// return the complete body of the specified news
		protected string GetNewsText(int newsID)
		{
			return new Business.News(newsID).Body;
		}

		#region Web Form Designer generated code
		override protected void OnInit(EventArgs e)
		{
			//
			// CODEGEN: This call is required by the ASP.NET Web Form Designer.
			//
			base.OnInit(e);
			InitializeComponent();
			
		}
		
		/// <summary>
		/// Required method for Designer support - do not modify
		/// the contents of this method with the code editor.
		/// </summary>
		private void InitializeComponent()
		{    
			this.Load += new System.EventHandler(this.Page_Load);

		}
		#endregion
	}
}