WPF 动态下拉+下拉点击事件

WPF 动态下拉+下拉点击事件

一、WPF动态下拉实现（①下拉死数据+②下拉数据通过数据库获取）

1、xaml中编辑         ---②中的灰色字体有误，不加那个触发器，绑定下拉数据也是通过SelectedValue={Binding ……}来实现双向绑定的

     <ComboBox materialDesign:HintAssist.Hint="采购类型" Text="{Binding BuyType}">
                <ComboBoxItem Content="新品进货" />
                <ComboBoxItem Content="缺货补货" />
            </ComboBox>
            


            <ComboBox
                Width="256"
                materialDesign:HintAssist.Hint="供应商"
                materialDesign:TextFieldAssist.HasClearButton="True"
                DisplayMemberPath="Supplier_Name"
                ItemsSource="{Binding SupplierInfo}"
                SelectedValue="{Binding SelectSupplierId}"
                SelectedValuePath="Id">
                <selectClick:Interaction.Triggers>
                    <selectClick:EventTrigger EventName="LostFocus">
                        <command:ExecuteCommandAction Command="{Binding SupplierClicked}" CommandParameter="{Binding SupplierInfo}" />
                    </selectClick:EventTrigger>
                </selectClick:Interaction.Triggers>
            </ComboBox>

 正确参考：

 

 

2、对应.cs文件实现下拉数据绑定

  //供应商
        public List<Supplier> _SupplierInfo { get; set; }
        public List<Supplier> SupplierInfo
        {
            get => _SupplierInfo; set
            {
                _SupplierInfo = value;
                RaisePropertyChanged();
            }
        }

3、实现绑定

 

二、下拉点击事件

 https://blog.csdn.net/wushang923/article/details/9243885

1、新建一个类编写下拉触发事件方法--网站中拷贝

 /// <summary>
    /// 下拉框触发事件
    /// </summary>
    public class ExecuteCommandAction:TargetedTriggerAction<UIElement>
    {

            public static readonly DependencyProperty CommandProperty =
            DependencyProperty.RegisterAttached("Command", typeof(ICommand), typeof(ExecuteCommandAction), new FrameworkPropertyMetadata(null));
            /// <summary> 命令
            /// </summary>
            public ICommand Command
            {
                get { return (ICommand)GetValue(CommandProperty); }
                set { SetValue(CommandProperty, value); }
            }


            public static readonly DependencyProperty CommandParameterProperty =
            DependencyProperty.RegisterAttached("CommandParameter", typeof(object), typeof(ExecuteCommandAction), new FrameworkPropertyMetadata(null));
            /// <summary> 参数
            /// </summary>
            public object CommandParameter
            {
                get { return GetValue(CommandParameterProperty); }
                set { SetValue(CommandParameterProperty, value); }
            }


            /// <summary>由给定的路由事件触发，参数是事件的发送方
            /// </summary>
            protected override void Invoke(object parameter)
            {
                if (Command == null) return;
                if (Command.CanExecute(CommandParameter))
                {
                    Command.Execute(CommandParameter);
                }
            }
        }

 

 

2、XAML窗体布局设计+文件类声明引用

 

    xmlns:command="clr-namespace:GroupThreeObject02WindosWPF.Common.ComboBox_Command_Binding"

 <ComboBox
                Width="256"
                materialDesign:HintAssist.Hint="供应商"
                materialDesign:TextFieldAssist.HasClearButton="True"
                DisplayMemberPath="Supplier_Name"
                ItemsSource="{Binding SupplierInfo}"
                SelectedValue="{Binding SelectSupplierId}"
                SelectedValuePath="Id">
                <selectClick:Interaction.Triggers>
                    <selectClick:EventTrigger EventName="LostFocus">
                        <command:ExecuteCommandAction Command="{Binding SupplierClicked}" CommandParameter="{Binding SupplierInfo}" />
                    </selectClick:EventTrigger>
                </selectClick:Interaction.Triggers>
            </ComboBox>

 

更正部分代码：

正确参考：

 

 

3、.cs文件事件Command命令事件

 

        //委托
        public DelegateCommand SupplierClicked { get; private set; }

        //供应商下拉选中ID
        public int _SelectSupplierId { get; set; }
        public int SelectSupplierId
        {
            get => _SelectSupplierId; set
            {
                _SelectSupplierId = value;
                RaisePropertyChanged();
            }
        }
        /// <summary>
        /// 供应商下拉点击事件
        /// </summary>
        void SupplierClickedExcute()
        {
            //var ii = i;
            foreach (var i in _SupplierInfo)
            {
                var ii = SelectSupplierId;
                if (i.Id == ii)
                {
                    //供应商赋值
                    _Supplier = i.Supplier_Name;
                }
            }

        }

 

 

4、实现下拉触发事件--此时完成了通过触发了下拉点击事件，返填上了其他数据