wpf之IValueConverter接口

向右看齐 2022-08-09 15:58 123阅读 0赞

wpf使用绑定数据源和每一列的值。这个方法虽然很方便，但有一个弊端。数据库中是什么数据，界面上显示的就是什么。如图，这样显示就非常不友好。

![Center][]

由此，想到了要转换。正好，wpf为我们提供了一个[IValueConverter 接口][IValueConverter]和一个[Binding.Converter 属性][Binding.Converter]。

后台代码：

//实现数据转化
        public class DataConverter:IValueConverter
        {
            //实现接口的两个方法
            #region IValueConverter 成员
    
            public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
            {
                string TypeInt = value.ToString();
                string TypeStr = string.Empty;
                switch (TypeInt)
                {
                    case "0":
                        TypeStr = "单个学校（单位）";
                        break;
                    case "1":
                        TypeStr = "教育行政部门";
                        break;
                }
    
                return TypeStr;
            }
    
            public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
            {
                string TypeStr = value.ToString();
                int TypeInt = 0;
                switch (TypeStr)
                {
                    case "单个学校（单位）":
                        TypeInt = 0;
                        break;
                    case "教育行政部门":
                        TypeInt = 1;
                        break;
                }
    
                return TypeInt;
            }
    
            #endregion
        }

界面代码：

<mdi:MdiChild xmlns:my="clr-namespace:Founder.CustomControl;assembly=Founder.CustomControl"  x:Class="Founder.Module2015.ztgl.Ztgl_2015"
                 xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                 xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                 xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
                 xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
                 xmlns:local="clr-namespace:Founder.Module2015.ztgl"    
                 xmlns:mdi="clr-namespace:WPF.MDI;assembly=WPF.MDI"
                 xmlns:cmd="clr-namespace:GalaSoft.MvvmLight.Command;assembly=GalaSoft.MvvmLight.Extras.WPF4"
                 xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"
                  xmlns:ctrls="clr_namespace:Founder.Controls"
                 mc:Ignorable="d" 
                 d:DesignHeight="300" d:DesignWidth="300" Height="500" Width="800">
        <mdi:MdiChild.Resources>
            <local:DataConverter x:Key="myTitleConverter"></local:DataConverter>
        </mdi:MdiChild.Resources>
    
     <DataGrid Grid.Row="1" x:Name="dgData"
                      AutoGenerateColumns="False"
                      CanUserAddRows="False"
                      EnableColumnVirtualization="True"
                      GridLinesVisibility="Horizontal"
                      ItemsSource="{Binding ZhangTaoSource,UpdateSourceTrigger=PropertyChanged,Mode=TwoWay}"
                      SelectedItem="{Binding SelectedZhangTao, Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}"
                                  SelectionMode="Single" SelectionUnit="FullRow">
                    <i:Interaction.Triggers>
                        <i:EventTrigger EventName="MouseDoubleClick">
                            <cmd:EventToCommand Command="{Binding ZTDoubleClick}" PassEventArgsToCommand="True"/>
                        </i:EventTrigger>
                    </i:Interaction.Triggers>
                    <DataGrid.Columns>
                        <DataGridTextColumn Binding="{Binding Name}" Width="*" Header="账套名称" IsReadOnly="True" />
                        <DataGridTextColumn Binding="{Binding Path=Type,Converter={StaticResource myTitleConverter}}" Width="*" Header="用户类型" IsReadOnly="True" />
                        <DataGridTextColumn Binding="{Binding DQDM}" Width="*" Header="地区代码" IsReadOnly="True" />
                        <DataGridTextColumn Binding="{Binding DQMC}" Width="*" Header="地区名称" IsReadOnly="True" />
                    </DataGrid.Columns>
                </DataGrid>
    
    </mdi:MdiChild>

结果：

![Center 1][]

[Center]: /images/20220731/2d27f8efa63e4ec9895c7ef487fb2576.png
[IValueConverter]: https://msdn.microsoft.com/zh-cn/library/system.windows.data.ivalueconverter.aspx
[Binding.Converter]: https://msdn.microsoft.com/zh-cn/library/vstudio/system.windows.data.binding.converter.aspx
[Center 1]: /images/20220731/e0c6d3c458054c59bad4ff15f54d69e7.png