关于c#：按钮命令以选择列表框中的下一个/上一个项目

Button command(s) to select next / previous item in ListBox

我是否可以使用一个按钮将一个简单的命令发送到标准WPF列表框，该按钮将使其选择列表中的下一个/上一个项目？

目前，我正在使用以下解决方案：

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哪个好。如果您在列表的第一项上(与最后一项相同)时单击上一个按钮，则确实会导致异常，但是当前计划是告诉它，如果selectedindex是列表中的第一项/最后一项，则禁用该按钮。列表。

我在问这个问题只是为了看看我是否比其他任何东西都缺少技巧。如果是这样，"不，那是不可能的，您必须以其他方式来做"是一个完全可以接受的答案。

使用mvvm会更好，更简单。这就是我要解决的方式。请注意，我的示例代码使用mvvmLight工具箱。

查看

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ViewModel

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using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Windows.Input;
using GalaSoft.MvvmLight;
using GalaSoft.MvvmLight.CommandWpf;

namespace StackOverFlow1.ViewModel
{

public class MainViewModel : ViewModelBase
{

public MainViewModel()
{
NextCommand=new RelayCommand<int>(OnNext,CanNext);
PreviousCommand=new RelayCommand<int>(OnPrevious,CanPrevious);
SelectedIndex = 0;

foreach (var student in GetStudent())
{
_students.Add(student);
}
}

public ICommand NextCommand { get; set; }
public ICommand PreviousCommand { get; set; }
private int _selectedIndex;

private List<Student> GetStudent()
{
return new List<Student>()
{
new Student {Id = 0,Name ="Kwame0"},
new Student {Id = 0,Name ="Kwame1"},
new Student {Id = 0,Name ="Kwame2"},
new Student {Id = 0,Name ="Kwame3"},
new Student {Id = 0,Name ="Kwame4"},
new Student {Id = 0,Name ="Kwame5"},
new Student {Id = 0,Name ="Kwame6"},
new Student {Id = 0,Name ="Kwame7"},
new Student {Id = 0,Name ="Kwame8"},
new Student {Id = 0,Name ="Kwame9"},
new Student {Id = 0,Name ="Kwame10"},
new Student {Id = 0,Name ="Kwame11"},
new Student {Id = 0,Name ="Kwame12"},
new Student {Id = 0,Name ="Kwame13"},
new Student {Id = 0,Name ="Kwame14"},
new Student {Id = 0,Name ="Kwame15"},
};
}
public int SelectedIndex
{
get { return _selectedIndex; }
set { _selectedIndex = value;RaisePropertyChanged(()=>SelectedIndex); }
}

private ObservableCollection<Student> _students=new ObservableCollection<Student>();

public ObservableCollection<Student> Students
{
get { return _students; }
set { _students = value; }
}

private void OnNext(int index)
{
if (SelectedIndex != Students.Count)
SelectedIndex += 1;
else
{
SelectedIndex = 0;
}
}

private bool CanNext(int indext)
{
return SelectedIndex != Students.Count;
}

private void OnPrevious(int index)
{
if (SelectedIndex != 0)
SelectedIndex -= 1;
else
{
SelectedIndex = Students.Count;
}
}

private bool CanPrevious(int index)
{
return SelectedIndex != 0;
}

}

public class Student
{
public int Id { get; set; }
public string Name { get; set; }

public override string ToString()
{
return $"{Id}-{Name}";
}
}
}