search.cs

微软的.NET论坛的源代码（COOL!!!）

        /// </summary>
        // ***********************************************************************/
        private void DisplaySearchResults() {
            // get the search results
            ToSearchEnum ToSearch;
            SearchWhatEnum SearchWhat;

            // determine what we want to search (post body or poster's username?)
            switch (Convert.ToInt32(searchFor.SelectedItem.Value)) {
                case 1:
                    ToSearch = ToSearchEnum.PostsBySearch;
                    break;

                default:
                    ToSearch = ToSearchEnum.PostsSearch;
                    break;
            }

            // determine how we want to search
            switch (Convert.ToInt32(matchingWords.SelectedItem.Value)) {
                case 1:
                    SearchWhat = SearchWhatEnum.SearchAnyWord;
                    break;

                case 2:
                    SearchWhat = SearchWhatEnum.SearchExactPhrase;
                    break;

                default:
                    SearchWhat = SearchWhatEnum.SearchAllWords;
                    break;
            }
				
            // Clean up search text
            textToSearchFor.Text = textToSearchFor.Text.Replace("'","''");

            // Perform the Search
             PostCollection posts = AspNetForums.Search.PerformSearch(ToSearch, SearchWhat,
                Convert.ToInt32(forumsToSearch.SelectedItem.Value),
                textToSearchFor.Text, searchResultsDataGrid.CurrentPageIndex+1, searchResultsDataGrid.PageSize);

            // if the dataset is empty, show an appropriate message
            if (posts.Count == 0) {
                ((Label) FindControl("lblNoResults")).Visible = true;				
                ((Panel) FindControl("panelSearchResults")).Visible = false;
            }
            else {	
                // we have results, bind it to the DataGrid.
                ((Panel) FindControl("panelSearchResults")).Visible = true;
                ((Label) FindControl("lblNoResults")).Visible = false;
			
                // see if we have more records to show...
                searchResultsDataGrid.VirtualItemCount = posts.TotalRecordCount;
			
                searchResultsDataGrid.DataSource = posts;
                searchResultsDataGrid.DataBind();
			
                // display how many results we got and what page we're viewing.
                ((Label) FindControl("lblInformation")).Text = String.Format("{0:d}", posts.TotalRecordCount) + " matches found.  Viewing Page " + (searchResultsDataGrid.CurrentPageIndex+1) + " of " + searchResultsDataGrid.PageCount;
            }
        }

        // *********************************************************************
        //  OnPreRender
        //
        /// <summary>
        /// This event handler checks to see if its the first time the page has
        /// been loaded - if it is, the data is bound.
        /// </summary>
        // ***********************************************************************/
        protected override void OnPreRender(EventArgs e) {

            // see if this is our first visit to the page
            if (!Page.IsPostBack) {
                DropDownList forumsToSearch = (DropDownList) FindControl("forumsToSearch");

                // If we found the control
                if (forumsToSearch != null) {
                    forumsToSearch.DataSource = Forums.GetAllForums();
                    forumsToSearch.DataBind();
                }

                // add the "All Forums" option if the user is allowed to search all forums
                if (AllowSearchAllForums)
                    forumsToSearch.Items.Insert(0, new ListItem("All Forums", "-1"));

                if (CheckForPassedInParameters())
                    DisplaySearchResults();
            }
        }


        // *********************************************************************
        //  CheckForPassedInParameters
        //
        /// <summary>
        /// This function checks to see if any querystring parameters were passed
        /// in.  Since we want to be able to invoke the search via a direct link, we need
        /// to allow querystring/form parameters to trip the search.  If a querystring/
        /// form parameter Contents is passed in, the search is automagically performed.
        /// </summary>
        // ***********************************************************************/
        private bool CheckForPassedInParameters() {

            if (Context.Request.Params["SearchText"] != null) {
                // we have parameter values!
                textToSearchFor.Text = Context.Request.Params["SearchText"].ToString();

                if (Context.Request.Params["SearchFor"] != null)
                    try {
                        searchFor.Items.FindByValue(Context.Request.Params["SearchFor"].ToString()).Selected = true;
                    } catch (Exception exp) {
                        exp = null;
                        searchFor.Items[0].Selected = true;
                    }
                else
                    searchFor.Items[0].Selected = true;
				
                if (Context.Request.Params["Forum"] != null)
                    try {
                        forumsToSearch.Items.FindByValue(Context.Request.Params["Forum"].ToString()).Selected = true;
                    } catch (Exception exp) {
                        exp = null;
                        forumsToSearch.Items[0].Selected = true;
                    }
                else
                    forumsToSearch.Items[0].Selected = true;

                if (Context.Request.Params["Results"] != null)
                    try {
                        resultsPerPage.Items.FindByValue(Context.Request.Params["Results"].ToString()).Selected = true;
                    } catch (Exception exp) {
                        exp = null;
                        resultsPerPage.Items[1].Selected = true;
                    }
                else
                    resultsPerPage.Items[1].Selected = true;
				
                if (Context.Request.Params["Matching"] != null)
                    try {
                        matchingWords.Items.FindByValue(Context.Request.Params["Matching"].ToString()).Selected = true;
                    } catch (Exception exp) {
                        exp = null;
                        matchingWords.Items[0].Selected = true;
                    }
                else
                    matchingWords.Items[0].Selected = true;
			
                // Set the Records per page
                searchResultsDataGrid.CurrentPageIndex = 0;
                searchResultsDataGrid.PageSize = Convert.ToInt32(resultsPerPage.SelectedItem.Value);
			
                return true;
            }
		
            return false;		// no querystring values
        }


        /// <summary>
        /// The message to display when no results are found for a search.
        /// </summary>
        [
        Category("Style"),
        Description("The message to display when no results are found for a search."),
        DefaultValue("No records were found matching your search query.")
        ]
        public String NoRecordsFoundMessage {
            get {
                if (ViewState["noRecsFoundMsg"] == null) return defaultNoRecordsMessage;
                return (String) ViewState["noRecsFoundMsg"];
            }
            set { ViewState["noRecsFoundMsg"] = value; }
        }

        /// <summary>
        /// The title that should appear at the top of the search page.
        /// </summary>
        [
        Category("Style"),
        Description("The title that should appear at the top of the search page."),
        DefaultValue("Search")
        ]
        public String SearchTitle {
            get {
                if (ViewState["searchTitle"] == null) return defaultSearchTitle;
                return (String) ViewState["searchTitle"];
            }
            set { ViewState["searchTitle"] = value; }
        }

        /// <summary>
        /// Used to display advanced search options.
        /// </summary>
        [
        Description("Display advanced search options."),
        DefaultValue("Search")
        ]
        public bool DisplayAdvancedSearch {
            get {
                if (ViewState["displayAdvancedSearch"] == null) return true;
                return (bool) ViewState["displayAdvancedSearch"];
            }
            set { ViewState["displayAdvancedSearch"] = value; }
        }


        /// <summary>
        /// This property determines whether or not the user can search all forums or must search
        /// from a particular forum.  It defaults to true.
        /// </summary>
        /// <remarks>For sites with a large number of forums and a large number of posts with a large
        /// user base performing many searches, setting this property to false may help the overall
        /// performance of the site.</remarks>
        [
        Category("Style"),
        Description("Whether or not a user can search all forums."),
        DefaultValue(true)
        ]
        public bool AllowSearchAllForums {
            get {
                if (ViewState["allowSearchAllForums"] == null) return defaultAllowSearchAllForums;
                return (bool) ViewState["allowSearchAllForums"];
            }
            set { ViewState["allowSearchAllForums"] = value; }
        }

        /// <summary>
        /// Specifies the text for the button to launch the search.
        /// </summary>
        [
        Category("Style"),
        Description("Specifies the text for the button to launch the search."),
        DefaultValue(" Search ")
        ]
        public String SearchButtonText {
            get {
                if (ViewState["searchButtonTxt"] == null) return defaultSearchButtonText;
                return (String) ViewState["searchButtonTxt"];
            }
            set { ViewState["searchButtonTxt"] = value; }
        }


        /// <summary>
        /// Specifies how many columns the Containing text box should have.
        /// </summary>
        [
        Category("Style"),
        Description("Specifies how many columns the Containing text box should have."),
        DefaultValue(50)
        ]
        public int ContainingTextBoxColumns {
            get {
                if (ViewState["containingTextBoxColumns"] == null) return defaultContainingTextBoxColumns;
                return (int) ViewState["containingTextBoxColumns"];
            }
            set { ViewState["containingTextBoxColumns"] = value; }
        }

        /// <summary>
        /// Determines how many characters of the Body should be displayed.  This property setting only
        /// takes affect if the ShowBody property is set to true.
        /// <seealso cref="ShowBody"/>
        /// </summary>
        [
        Category("Style"),
        Description("Determines how many characters of the Body should be displayed."),
        DefaultValue(500)
        ]
        public int MaxBodyLengthToDisplay {
            get {
                if (ViewState["mblToDisplay"] == null) return defaultMaxBodyLength;
                return (int) ViewState["mblToDisplay"];
            }
            set { ViewState["mblToDisplay"] = value; }
        }

        /// <summary>
        /// Determines whether or not the Body of the message should be displayed in the search results.
        /// </summary>
        [
        Category("Style"),
        Description("Determines whether or not the Body of the message should be displayed."),
        DefaultValue(true)
        ]
        public bool ShowBody {
            get {
                if (ViewState["showBody"] == null) return defaultShowBody;
                return (bool) ViewState["showBody"];
            }
            set { ViewState["showBody"] = value; }
        }

        /// <summary>
        /// Specifies the UI and stylistic settings of the search results Pager.  The Pager allows the
        /// end user to navigate between multiple pages of search results.
        /// </summary>
        [
        Category("Style"),
        Description("Specifies the UI and stylistic settings of the search results Pager.")
        ]
        public SearchPagerStyle PagerStyle {
            get  {  return datagridPagerStyle;  }
        }
        /*******************************************************/
    }
}