C# Children.Add(item) 值不在预期范围内
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/1214173/
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
Children.Add(item) value does not fall within the expected range
提问by oltman
I'm developing a Silverlight 3 app and getting this really weird error when I try to add an object to a Canvas. My code is as follows:
我正在开发一个 Silverlight 3 应用程序，当我尝试将一个对象添加到 Canvas 时，遇到了这个非常奇怪的错误。我的代码如下：
for (int i = 0; i < person.Children.Count; i++)
{
//Add children in same position as parent
Person child = person.Children[i];
child.x_PositionTransform.X = person.x_PositionTransform.X;
child.x_PositionTransform.Y = person.x_PositionTransform.Y;
child.Click += new RoutedEventHandler(person_Click);
x_LayoutRoot.Children.Add(child);
}
The first time I use this, it works as expected. However, when I hit x_LayoutRoot.Children.Add(child) after clicking a Person object that was created using this code, I get an ArgumentException telling me that "Value does not fall within the expected range."
我第一次使用它时，它按预期工作。但是，当我在单击使用此代码创建的 Person 对象后点击 x_LayoutRoot.Children.Add(child) 时，我收到一个 ArgumentException，告诉我“值不在预期范围内”。
However, when I add the following code before adding child to x_LayoutRoot.Children, the problem disappears.
但是，当我在将 child 添加到 x_LayoutRoot.Children 之前添加以下代码时，问题就消失了。
child.SetValue(Canvas.NameProperty, "child" + objCount++);
Why is this happening? Is this a Silverlight bug, or (more likely) am I just missing something?
为什么会这样？这是 Silverlight 错误，还是（更有可能）我只是遗漏了什么？
采纳答案by oltman
I think I've figured out the cause of this: I was adding multiple Person objects with the same name. So, if anyone has this issue in the future, make sure all of your objects have unique names!
我想我已经找到了原因：我添加了多个具有相同名称的 Person 对象。因此，如果将来有人遇到此问题，请确保您的所有对象都有唯一的名称！
回答by senthil
Person child = person.Children[i];
child.x_PositionTransform.X = person.x_PositionTransform.X;
child.x_PositionTransform.Y = person.x_PositionTransform.Y;
child.Click += new RoutedEventHandler(person_Click);
child.SetValue(Canvas.NameProperty, "child" + objCount++); //!
x_LayoutRoot.Children.Add(child);
you can add different NamePropertybefore add a child
您可以NameProperty在添加孩子之前添加不同的
