使用 for 循环而不是 foreach 循环遍历 wpf 列表框
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/24062850/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Loop through wpf listbox using a for loop instead of a foreach loop
提问by Jan Solo
I have a c# wpf listbox and I am trying to get the values from the selected items. I cannot use a foreach loop (every value I find will remove an item from the listbox). But this seems impossible.
我有 ac# wpf 列表框，我正在尝试从所选项目中获取值。我不能使用 foreach 循环（我找到的每个值都会从列表框中删除一个项目）。但这似乎是不可能的。
What I want is somthing like this:
我想要的是这样的东西：
for (int i = <numberofselecteditems> - 1; i >= 0; i--)
{
string displaymembervalue = listbox.selecteditem[i].displaymembervalue;
}
I have a solution which involve to loop over all the listbox items twice. This is not really an option since it will slow the app too much.
我有一个解决方案，它涉及两次遍历所有列表框项目。这不是一个真正的选择，因为它会使应用程序减慢太多。
Like I said before, this is NOT the
就像我之前说的，这不是
System.Windows.Forms.Listbox
but the
但是
System.Windows.Controls.Listbox
thank you!!
谢谢你！！
J.
J。
回答by GEEF
See the solution here, it is essentially using a foreach in the follolwing fashion:
请参阅此处的解决方案，它本质上是以以下方式使用 foreach：
foreach (var item in listBox1.SelectedItems)
{
// Do what you want here... Console.WriteLine(item), etc.
}
If you really want to do it with a for loop rather than a foreach, then do the following:
如果你真的想用 for 循环而不是 foreach 来做，那么执行以下操作：
for(int i = selectedItems.Count - 1; i >= 0; --i)
{
var item = selectedItems[i];
// Do what you want with item
}
回答by Anthony Russell
Here is your XAML bound to a Observable collection
这是绑定到 Observable 集合的 XAML
<ListBox ItemsSource="{Binding items}"/>
Here is your observable collection of objects
这是您的可观察对象集合
private ObservableCollection<Object> _items;
public ObservableCollection<Object> items{
get{ return _items; }
}
Here is the enumeration over them and the removing of each item
这是对它们的枚举和每个项目的删除
for(int x = 0; x < _items.Count; x++){
_items.Remove(_items.Where(n => n == _items[x]).Single());
//You may have to do a notify property changed on this if the UI Doesnt update but thats easily googled.
//Traditionally it would update. However since you are bound to items Im not sure if it will update when you manipulate _items
}
回答by IdahoSixString
Alternatively instead of enumerating twice you can create a copy of the list of objects and then remove the items from the original list while still enumerating.
或者，您可以创建对象列表的副本，然后在仍然枚举的同时从原始列表中删除项目，而不是枚举两次。
foreach (var selectedItem in listBox1.SelectedItems.Cast<List>())
{
//remove items from the original list here
}
回答by Brian Watt
Create a second list. You still have to iterate twice, but the second iteration is not over the entire list of items.
创建第二个列表。您仍然需要迭代两次，但第二次迭代不会遍历整个项目列表。
var items List<ListBoxItem>;
foreach (var item in listbox1.SelectedItems)
items.Add(item);
foreach (var item in items)
listbox1.Remove(item);
