名詞解釋
DLR: dynamic language runtime.
refer to this article: http://msdn.microsoft.com/en-us/vstudio/ff800651.aspx
下面是一個簡單的實現(xiàn),會動態(tài)的創(chuàng)建需要的屬性:
class Program
{
static void Main(string[] args)
{
dynamic dynamicProperties = new MyDynamicObject();
try
{
Console.WriteLine(dynamicProperties.Marker);
}
catch (Microsoft.CSharp.RuntimeBinder.RuntimeBinderException)
{
Console.WriteLine("There is no such a property.");
}
dynamicProperties.Date = DateTime.Now;
dynamicProperties.Name = "Bill Wagner";
dynamicProperties.Title = "Effective C#";
dynamicProperties.Content = "Building a dynamic dictionary";
Console.WriteLine(dynamicProperties);
Console.ReadLine();
}
}
class MyDynamicObject : DynamicObject
{
private Dictionary<string, object> storage = new Dictionary<string, object>();
public override bool TryGetMember(GetMemberBinder binder, out object result)
{
if (storage.ContainsKey(binder.Name))
{
result = storage[binder.Name];
return true;
}
result = null;
return false;
}
public override bool TrySetMember(SetMemberBinder binder, object value)
{
string key = binder.Name;
if (storage.ContainsKey(key))
storage[key] = value;
else
storage.Add(key, value);
return true;
}
public override string ToString()
{
var sb = new StringBuilder();
foreach (var item in storage)
sb.AppendLine(string.Format("{0}:\t{1}", item.Key, item.Value));
return sb.ToString();
}
}
更比較通用的是ExpandoObject類,可以在運行是動態(tài)的添加或刪除成員,包括屬性,事件等等。
例如,
1. 添加新屬性:
dynamic sampleObject = new ExpandoObject();
sampleObject.test =
"Dynamic Property"
;
Console.WriteLine(sampleObject.test);
Console.WriteLine(sampleObject.test.GetType());
2.?添加事件(lambda或event):
// 2.1 add lambda expression
sampleObject.number = 10;
sampleObject.Increment = (Action)(() => { sampleObject.number++; });
// Before calling the Increment method.
Console.WriteLine(sampleObject.number);
sampleObject.Increment();
// After calling the Increment method.
Console.WriteLine(sampleObject.number);
// 2.2 add event
// Create a new event and initialize it with null. must declare it first.
sampleObject.sampleEvent =
null
;
?
// Add an event handler.
sampleObject.sampleEvent +=
new
EventHandler(SampleHandler);
?
// Raise an event for testing purposes.
sampleObject.sampleEvent(sampleObject,
new
EventArgs());
?
// Event handler.
?
static
void
SampleHandler(
object
sender, EventArgs e)
?{
??????? Console.WriteLine(
"SampleHandler for {0} event"
, sender);
}
3. 作為參數(shù)傳遞
dynamic employee =
new
ExpandoObject();
employee.Name =
"John Smith"
;
employee.Age = 33;
WritePerson(employee);
private static void WritePerson( dynamic person)
{
??????? Console.WriteLine(
"{0} is {1} years old."
, person.Name, person.Age);
}
4. 枚舉成員:
因為該類實現(xiàn)了IDictionary<string, object>接口,所以可以枚舉它的成員。
dynamic employee = new ExpandoObject();
employee.Name = "John Smith";
employee.Age = 33;
foreach (var property in (IDictionary<String, Object>)employee)
{
??? Console.WriteLine(property.Key + ": " + property.Value);
}
// This code example produces the following output:
// Name: John Smith
// Age: 33
// 刪除某個成員
dynamic employee = new ExpandoObject();
employee.Name = "John Smith";
((IDictionary<String, Object>)employee).Remove("Name");
5. 通知機制
// Add "using System.ComponentModel;" line
// to the beginning of the file.
class Program
{
??? static void Test()
??? {
??????? dynamic employee = new ExpandoObject();
??????? ((INotifyPropertyChanged)employee).PropertyChanged +=
??????????? new PropertyChangedEventHandler(HandlePropertyChanges);
??????? employee.Name = "John Smith";
??? }
??? private static void HandlePropertyChanges(
??????? object sender, PropertyChangedEventArgs e)
??? {
??????? Console.WriteLine("{0} has changed.", e.PropertyName);
??? }
}
?
?
更多文章、技術(shù)交流、商務(wù)合作、聯(lián)系博主
微信掃碼或搜索:z360901061
微信掃一掃加我為好友
QQ號聯(lián)系: 360901061
您的支持是博主寫作最大的動力,如果您喜歡我的文章,感覺我的文章對您有幫助,請用微信掃描下面二維碼支持博主2元、5元、10元、20元等您想捐的金額吧,狠狠點擊下面給點支持吧,站長非常感激您!手機微信長按不能支付解決辦法:請將微信支付二維碼保存到相冊,切換到微信,然后點擊微信右上角掃一掃功能,選擇支付二維碼完成支付。
【本文對您有幫助就好】元

