Question

我正试图从复选框中获取已检查的号码。

<Window x:Class="WpfApplication6.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:local ="clr-namespace:WpfApplication6"
        Title="MainWindow" Height="350" Width="525">
    <Window.Resources>
        <local:Test x:Key="TestContext"></local:Test>
    </Window.Resources>

    <Grid>
        <ListBox ItemsSource="{Binding TestList}">
            <ListBox.ItemTemplate>
                <DataTemplate>
                    <CheckBox Content="{Binding number}" Command="{Binding  WhatChecked,Source={StaticResource TestContext},Mode=OneWay}" IsChecked="{Binding check}" CommandParameter="{Binding check}"></CheckBox>
                </DataTemplate>
            </ListBox.ItemTemplate>
        </ListBox>
    </Grid>
</Window>

但我只能传递一个参数

using GalaSoft.MvvmLight.Command;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using System.Diagnostics;
namespace WpfApplication6
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
/// 
public class DataStruct
{
    public string number {get;set;}
    public bool check {get;set;}
}
public class Test
{
    public Test()
    {
        WhatChecked = new RelayCommand<bool>((e) => Show(e));
        DataStruct DS = new DataStruct();
        DS.check = false;
        DS.number = "101";
        DataStruct DS1 = new DataStruct();
        DS1.check = false;
        DS1.number = "102";
        DataStruct DS2 = new DataStruct();
        DS2.check = false;
        DS2.number = "103";
        testList = new List<DataStruct>();
        TestList.Add(DS);
        TestList.Add(DS1);
        TestList.Add(DS2);
    }
    public ICommand WhatChecked { get; set; }
    private List<DataStruct> testList;
    public List<DataStruct> TestList
    {
        get { return testList; }
        set { testList = value; }
    }
    private void Show(object param)
    {
        if (Convert.ToBoolean(param))
        {
            Debug.WriteLine("Clicked: {0}", param);
        }
    }
}
public partial class MainWindow : Window
{
    public MainWindow()
    {
        InitializeComponent();
        this.DataContext = new Test();
    }
}

}

但我不能将带有数字的字符串传递给命令参数，因为我已经有参数。

Answer 1

由于所有项目都在列表中，并且所有项目都绑定到复选框IsChecked属性，因此您只需使用LINQ搜索列表

TestList.Where(p=>p.check).Count();

Answer 2

如果将CommandParameter绑定设置为{Binding}，那么它将传递CheckBox的DataContext（即整个DataStruct对象）作为参数。这应该允许您访问所有DataStruct属性，而不仅仅是检查。请注意，许多人认为这违反了MVVM原则，因为ViewModel变得更紧密地依赖于View /依赖于View。我已经使用过这种方法几次，我认为有必要完成工作。

<CheckBox Content="{Binding number}" Command="{Binding WhatChecked,Source={StaticResource TestContext},Mode=OneWay}" IsChecked="{Binding check}" CommandParameter="{Binding}"></CheckBox>

如何计算已选中复选框WPF

2 个答案: