项目中查询数据和模糊查询

Posted 2022-12-03 weixin_44543308

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开发工具与关键技术：WPF 、Select

撰写日期：2020年08月07日

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 一、 在项目中要查询出数据要做四个步骤：1、先是搭建好页面、2、去数据库写存储过程、3、在服务端写对应的方法之后发布服务、4、最后到客户端写查询方法

1. 首先来看页面搭建，如下：

<!--页面布局-->

    <DockPanel>

        <DockPanel DockPanel.Dock="Top">

            <!--三行-->

            <Grid>

                <Grid.RowDefinitions>

                    <RowDefinition Height="1*"></RowDefinition>

                    <RowDefinition Height="1*"></RowDefinition>

                    <RowDefinition Height="12*"></RowDefinition>

                </Grid.RowDefinitions>

                <!--菜单按钮-->

                <WrapPanel Orientation="Horizontal" 

                           HorizontalAlignment="Right">

                    <Button Content="添加新闻" Style="StaticResource BtnInsertStyle" Margin="2" Name="btnInsert" Click="btnInsert_Click"></Button>

                    <Button Content="修改新闻" Style="StaticResource BtnUpdateStyle" Margin="2" Name="btnUpdate" Click="btnUpdate_Click"></Button>

                    <Button Content="删除" Style="StaticResource BtnDeleteStyle" Margin="2" Name="btnDelete" Click="btnDelete_Click"></Button>

                </WrapPanel>

                <!--搜索栏-->

                <WrapPanel Grid.Row="1" HorizontalAlignment="Center"

                           VerticalAlignment="Center">

                    <TextBlock Text="搜索：" Foreground="Black"></TextBlock>

                    <TextBox x:Name="txt_Select" ToolTip="请输入：新闻标题\\新闻分类\\发布人" Width="300" Height="23" Background="Transparent" SelectionChanged="txtSelect_SelectionChanged" HorizontalAlignment="Left" VerticalAlignment="Center"></TextBox>

                </WrapPanel>

                <!--表格数据-->

                <Grid Grid.Row="2" VerticalAlignment="Stretch">

                    <GroupBox Header="新闻信息" Foreground="Black">

                        <DataGrid x:Name="dgNews" IsReadOnly="True" HorizontalAlignment="Stretch" AutoGenerateColumns="False" CanUserAddRows="False" CanUserReorderColumns="False" CanUserResizeColumns="False" CanUserResizeRows="False" SelectionMode="Single" AlternationCount="2" RowHeaderWidth="0"  Background="White" SelectedCellsChanged="dgNews_SelectedCellsChanged">

                            <DataGrid.Columns>

                                <DataGridTextColumn Header="序号" x:Name="number" Binding="Binding number" Width="80"/>

                                <DataGridTextColumn Header="新闻类型ID" Binding="Binding NewsTypeID" Visibility="Collapsed" Width="10"/>

                                <DataGridTextColumn Header="新闻分类" Binding="Binding NewsTypeName" Width="150"/>

                                <DataGridTextColumn Header="新闻标题" Binding="Binding NewsHeadline" Width="150"/>

                                <DataGridTextColumn Header="发布人" Binding="Binding PowerName" Width="150"/>

                                <DataGridTextColumn Header="权限ID" Binding="Binding PowerID" Visibility="Collapsed" Width="10"/>

                                <DataGridTextColumn Header="来源" Binding="Binding Sources" Width="150"/>

                                <DataGridTextColumn Header="是否固顶" Binding="Binding SolidRoof" Width="150"/>

                                <DataGridTextColumn Header="是否推荐" Binding="Binding Recommend" Width="150"/>

                                <DataGridTextColumn Header="发布时间" Binding="Binding ReleaseTime,StringFormat=\\0:yyyy-MM-dd HH:mm:ss\\" Width="200"/>

                                <DataGridTextColumn Header="新闻内容" Binding="Binding NewsContent" Width="250"></DataGridTextColumn>

                            </DataGrid.Columns>

                        </DataGrid>

                    </GroupBox>

                </Grid>

            </Grid>

        </DockPanel>

</DockPanel>

1. 搭完就去数据库中写查询的存储过程，如下图：

   

 

3、把数据库查询的方法绑定到服务端中，刚开始写的时候必须要引入[ServiceContract]服务契约还有一个是操作契约 [OperationContract]，你没写一个方法都必须要写操作契约，如果没写就会报错

，如下：

 //服务契约

    [ServiceContract]

    public class Journalism

    

        // 实例化数据层

        DAL.DALMethod myDALMethod = new DAL.DALMethod();

        //操作契约

        [OperationContract]

          //查询新闻信息

        public DataSet UserControl_Select_Journalism()

        

            SqlParameter[] myJournalism =

                new SqlParameter("@type",SqlDbType.Char),  ;

            myJournalism[0].Value = "UserControl_Select_Journalism";

            DataSet myDataSet = myDALMethod.QueryDataSet("UC_Journalism", myJournalism);

            return myDataSet;  

4、写好之后就去发布服务，再到客户端引用服务，最后写查询数据方式，如下：

   引用布局变量（服务端的方法）

     BLL.Journalism.JournalismClient myClient = new BLL.Journalism.JournalismClient();

        DataTable dt;

接着就是查询数据了

//封装刷新页面数据查询

        public void GetDataTable()

        

            dt = myClient.UserControl_Select_Journalism().Tables[0];

            dgNews.ItemsSource = dt.DefaultView;

1. 结果如下

   

 

• 模糊查询方法如下：

 //搜索栏加载事件

        private void txtSelect_SelectionChanged(object sender, RoutedEventArgs e)

        

            //声明变量

            string select = "";

            //获取控件数据

            string strSt = txt_Select.Text.Trim();

            //判断不能为空

            if (strSt != "")  

                //模糊查询内容

                select += "NewsHeadline like '%" + strSt + "%'" +

                          "or NewsTypeName like '%" + strSt + "%'" +

                          "or PowerName like '%" + strSt + "%'";

            //获取表格全部数据

            DataTable dtSelect = myClient.UserControl_Select_Journalism().Tables[0];

            //实例化视图（把表格数据化为视图）

            DataView dv = new DataView(dtSelect);

            DataTable dt = new DataTable();

            //判断添加不存在

            if (select != "")

                //调用视图的筛选数据

                dv.RowFilter = select;

                //再把视图转化为表格

                dt = dv.ToTable();  

            if (select == "")

                //查询全部数据

                dt = dv.ToTable();

            //绑定控件数据

            dgNews.ItemsSource = dt.DefaultView;

        

结果图如下：