ASP.NET网站全文检索（代码部分）

ASPX页面代码如下：

<tr>
    <td class="record" height="20">关 键 词：
    <asp:textbox id="txtQuery" accessKey="Q" runat="server" Width="250px" MaxLength="50"></asp:textbox>&nbsp;
    <asp:button id="btnSearch" runat="server" Text="搜索" EnableViewState="False"></asp:button></td>
</tr>
<tr>
    <td height="10">查询方式：
    <asp:dropdownlist id="cboQueryType" accessKey="T" runat="server" Width="250px" EnableViewState="False">
    <asp:ListItem Value="All" Selected="True">包含全部的字词</asp:ListItem>
    <asp:ListItem Value="Any">包含任何一个字词</asp:ListItem>
    <asp:ListItem Value="Boolean">布尔表达式查询</asp:ListItem>
    <asp:ListItem Value="Exact">全字匹配</asp:ListItem>
    <asp:ListItem Value="Natural">自然语言查询</asp:ListItem>
    </asp:dropdownlist>
    </td>
</tr>
<tr>
    <td class="record" height="20">查询范围：
    <asp:dropdownlist id="cboDirectory" accessKey="D" runat="server" Width="250px" EnableViewState="False">
    <asp:ListItem Value="/" Selected="True">整个网站</asp:ListItem>
    </asp:dropdownlist>
    </td>
</tr>
<tr>
    <td class="record" height="20"><asp:label id="lblResultCount" runat="server" Font-Italic="True" visible="False" EnableViewState="False"></asp:label></td>
</tr>
<tr>
    <td vAlign="top" height="210">
    <asp:datagrid id="dgResultsGrid" runat="server" PageSize="15" AllowPaging="True" AutoGenerateColumns="False"
        Visible="False" GridLines="None" EnableViewState="False">
        <ItemStyle HorizontalAlign="Left" VerticalAlign="Top"></ItemStyle>
        <HeaderStyle Font-Bold="True"></HeaderStyle>
        <Columns>
            <asp:TemplateColumn HeaderText="排名">
                <HeaderStyle Width="40px"></HeaderStyle>
                <ItemTemplate>
                    <%# (cint(DataBinder.Eval(Container, "DataSetIndex"))) + 1 %>
                    </ItemTemplate>
                    </asp:TemplateColumn>
                    <asp:TemplateColumn HeaderText="文档信息">
                    <ItemStyle HorizontalAlign="Left" VerticalAlign="Top"></ItemStyle>
                    <ItemTemplate>
                    <p>
                    <a href='<%# DataBinder.Eval(Container.DataItem, "VPath")%>' target="_blank">
                    <%# GetTitle(Container.DataItem)%>
                    </a>
                    <br>
                    <%# GetCharacterization(Container.DataItem)%>
                    <br>
                    <i><a href='<%# DataBinder.Eval(Container.DataItem, "VPath")%>' target="_blank">http://<%# Request.ServerVariables("SERVER_NAME")%><%# DataBinder.Eval(Container.DataItem, "VPath")%></a>
                    -
                    <%# GetFileSize(Container.DataItem)%>
                    k </i>
                    </p>
                </ItemTemplate>
            </asp:TemplateColumn>
            </Columns>
        <PagerStyle Visible="False"></PagerStyle>
    </asp:datagrid>
    </td>
</tr>

后台代码，使用VB.NET书写：

 

 ' 绑定查询结果
        Private Sub BindSearch()Sub BindSearch()

            Dim dbAdapter As OleDbDataAdapter = New System.Data.OleDb.OleDbDataAdapter
            Dim oleDbSelectCommand1 As OleDbCommand = New System.Data.OleDb.OleDbCommand
            Dim dbConnection As OleDbConnection = New System.Data.OleDb.OleDbConnection
            Dim ds As DataSet = New DataSet("Results")
            Dim rows As Integer = 0

            dbAdapter.SelectCommand = oleDbSelectCommand1
            oleDbSelectCommand1.Connection = dbConnection
            dbConnection.ConnectionString = "Provider=MSIDXS.1;Integrated Security .='';Data Source=Web"

            Try
                dbAdapter.SelectCommand.CommandText = Command
                If CStr(ViewState("KEY")) <> "" Then
                    dbAdapter.Fill(ds)
                    rows = ds.Tables(0).Rows.Count
                Else
                    lblResultCount.Text = "请输入关键词进行查询！"
                End If

                If Not ds Is Nothing AndAlso rows > 0 Then
                    ' 自定义分页，与查询逻辑无关
                    ViewState("TOTALROWS") = rows
                    CalculatePage()

                    dgResultsGrid.AllowPaging = True
                    dgResultsGrid.PageSize = CInt(ViewState("PAGESIZE"))
                    dgResultsGrid.CurrentPageIndex = CInt(ViewState("PAGEINDEX")) - 1

                    lblResultCount.ForeColor = Color.Black
                    lblResultCount.Text = String.Format("找到 {0} 个相关网页", rows)

                    dgResultsGrid.DataSource = ds
                    dgResultsGrid.DataBind()
                    dgResultsGrid.Visible = (rows > 0)
                Else
                    ViewState("TOTALROWS") = 0
                    CalculatePage()
                End If

            Catch ex As Exception
                lblResultCount.ForeColor = Color.Red
                lblResultCount.Text = String.Format("无法执行特定的查询: {0}", ex.Message)
                dgResultsGrid.Visible = False
            Finally
                lblResultCount.Visible = True
            End Try
            ' 自定义分页
            BindNavigate()

        End Sub

 

Private ReadOnly Property Command()Property Command() As String
            Get
                Dim query As String
                query = String.Format("SELECT Rank, VPath, DocTitle, Filename, Size, Characterization, Write FROM SCOPE('DEEP TRAVERSAL OF ""{0}""') WHERE  Not CONTAINS(FileName,'""*.txt"" OR ""*.js"" OR ""*.css"" OR ""*.config"" OR ""*.xml""')", CStr(ViewState("DIR")))

                Dim type As String = CStr(ViewState("TYPE")).ToLower()
                Dim fmt As String = " AND (CONTAINS('{0}') OR CONTAINS(DocTitle, '{0}'))"
                Dim text As String = CStr(ViewState("KEY")).Replace(";", "").Trim

                If type = "all" Or type = "any" Or type = "boolean" Then
                    Dim words() As String = Split(text, " ")
                    Dim len As Integer = words.Length
                    Dim i As Integer

                    For i = 0 To len - 1 Step i + 1
                        Dim word As String = words(i)
                        If type = "boolean" AndAlso (String.Compare(word, "and", True) = 0 OrElse String.Compare(word, "or", True) = 0 OrElse String.Compare(word, "not", True) = 0 OrElse String.Compare(word, "near", True) = 0) Then
                        ElseIf word <> "" Then
                            words(i) = String.Format("""{0}""", word)

                            If i < len - 1 Then
                                If type = "all" Then
                                    words(i) += " AND"
                                ElseIf type = "any" Then
                                    words(i) += " OR"
                                End If
                            End If
                        End If
                    Next

                    query += String.Format(fmt, String.Join(" ", words))

                ElseIf type = "exact" Then
                    query += String.Format(fmt, text)
                ElseIf type = "natural" Then
                    query += String.Format(" AND FREETEXT('{0}')", text)
                End If

                query += " ORDER BY Rank DESC"

                Return query
            End Get
        End Property

 

        ' 如果网页没有Title，那么使用文件名
        Protected Function GetTitle()Function GetTitle(ByVal value As Object) As Object
            Dim title As String = Convert.ToString(DataBinder.Eval(value, "DocTitle"))

            If Not (title Is Nothing) And title.Length > 0 Then
                Return title '
            Else
                Return DataBinder.Eval(value, "Filename")
            End If
        End Function 'GetTitle

        ' 取摘要
        Protected Function GetCharacterization()Function GetCharacterization(ByVal value As Object) As String
            Return Server.HtmlEncode(Convert.ToString(DataBinder.Eval(value, "Characterization")))
        End Function

        ' 取文件尺寸，单位KB
        Protected Function GetFileSize()Function GetFileSize(ByVal value As Object) As String
            Return Convert.ToString(CInt(Convert.ToInt32(DataBinder.Eval(value, "Size")) / 1000))
        End Function