常规用法：
Type t = sender.GetType();
if (t == typeof(Button)) {
var realObj = (Button)sender;
// Do Something
}
else if (t == typeof(CheckBox)) {
var realObj = (CheckBox)sender;
// Do something else
}
else {
// Default action
}
非常规方法一：
TypeSwitch.Do(
sender,
TypeSwitch.Case<Button>(() => textBox1.Text = "Hit a Button"),
TypeSwitch.Case<CheckBox>(x => textBox1.Text = "Checkbox is " + x.Checked),
TypeSwitch.Default(() => textBox1.Text = "Not sure what is hovered over"));
相应的静态类
static class TypeSwitch {
public class CaseInfo {
public bool IsDefault { get; set; }
public Type Target { get; set; }
public Action<object> Action { get; set; }
}
public static void Do(object source, params CaseInfo[] cases) {
var type = source.GetType();
foreach (var entry in cases) {
if (entry.IsDefault || type == entry.Target) {
entry.Action(source);
break;
}
}
}
public static CaseInfo Case<T>(Action action) {
return new CaseInfo() {
Action = x => action(),
Target = typeof(T)
};
}
public static CaseInfo Case<T>(Action<T> action) {
return new CaseInfo() {
Action = (x) => action((T)x),
Target = typeof(T)
};
}
public static CaseInfo Default(Action action) {
return new CaseInfo() {
Action = x => action(),
IsDefault = true
};
}
}方法二：
定义：var @switch = new Dictionary<Type, Action> {
{ typeof(Type1), () => ... },
{ typeof(Type2), () => ... },
{ typeof(Type3), () => ... },
};@switch[typeof(MyType)]();
使用：
if(@switch.ContainsKey(typeof(MyType))) {
@switch[typeof(MyType)]();
}