用字符串(反射)从c#动态对象中获取属性值

Assume that I have a dynamic variable:

假设我有一个动态变量:

dynamic d = *something*

Now, something creates properties to d which I have on the other hand from a string array:

现在，我从一个字符串数组中，从另一个角度来创建属性d

string[] strarray = { 'property1','property2',..... }

I don't know the property names in advance.

我不提前知道物业的名称。

How in code, once d is created and strarray is pulled from DB, can I get the values?

在代码中，一旦创建了d，从DB中提取了strarray，我能得到值吗?

I want to get d.property1 , d.property2.

我想要d。property1 d.property2。

I see that the object has a _dictionary internal dictionary that contains the keys and the values, how do I retrieve them?

我看到对象有一个包含键和值的_dictionary内部字典，如何检索它们?

8 个解决方案

#1

I don't know if there's a more elegant way with dynamically created objects, but using plain old reflection should work:

我不知道动态创建对象是否有更优雅的方式，但是使用普通的旧反射应该工作:

var nameOfProperty = "property1";
var propertyInfo = myObject.GetType().GetProperty(nameOfProperty);
var value = propertyInfo.GetValue(myObject, null);

GetProperty will return null if the type of myObject does not contain a public property with this name.

如果myObject类型不包含具有此名称的公共属性，则GetProperty将返回null。

EDIT: If the object is not a "regular" object but something implementing IDynamicMetaObjectProvider, this approach will not work. Please have a look at this question instead:

编辑:如果对象不是“常规”对象，而是实现IDynamicMetaObjectProvider的东西，则此方法将不起作用。请看看这个问题:

How do I reflect over the members of dynamic object?
如何反映动态对象的成员?

#2

This will give you all property names and values defined in your dynamic variable.

这将给您提供在动态变量中定义的所有属性名和值。

dynamic d = { // your code };
object o = d;
string[] propertyNames = o.GetType().GetProperties().Select(p => p.Name).ToArray();
foreach (var prop in propertyNames)
{
    object propValue = o.GetType().GetProperty(prop).GetValue(o, null);
}

#3

Hope this would help you:

希望这对你有帮助:

public static object GetProperty(object o, string member)
{
    if(o == null) throw new ArgumentNullException("o");
    if(member == null) throw new ArgumentNullException("member");
    Type scope = o.GetType();
    IDynamicMetaObjectProvider provider = o as IDynamicMetaObjectProvider;
    if(provider != null)
    {
        ParameterExpression param = Expression.Parameter(typeof(object));
        DynamicMetaObject mobj = provider.GetMetaObject(param);
        GetMemberBinder binder = (GetMemberBinder)Microsoft.CSharp.RuntimeBinder.Binder.GetMember(0, member, scope, new CSharpArgumentInfo[]{CSharpArgumentInfo.Create(0, null)});
        DynamicMetaObject ret = mobj.BindGetMember(binder);
        BlockExpression final = Expression.Block(
            Expression.Label(CallSiteBinder.UpdateLabel),
            ret.Expression
        );
        LambdaExpression lambda = Expression.Lambda(final, param);
        Delegate del = lambda.Compile();
        return del.DynamicInvoke(o);
    }else{
        return o.GetType().GetProperty(member, BindingFlags.Public | BindingFlags.Instance).GetValue(o, null);
    }
}

#4

string json = w.JSON;

var serializer = new JavaScriptSerializer();
serializer.RegisterConverters(new[] { new DynamicJsonConverter() });

DynamicJsonConverter.DynamicJsonObject obj = 
      (DynamicJsonConverter.DynamicJsonObject)serializer.Deserialize(json, typeof(object));

Now obj._Dictionary contains a dictionary. Perfect!

现在obj。_Dictionary包含一个字典。完美!

This code must be used in conjunction with Deserialize JSON into C# dynamic object? + make the _dictionary variable from "private readonly" to public in the code there

该代码必须与反序列化JSON一起使用到c#动态对象中?+使_dictionary变量从“private readonly”变为公共代码。

#5

Did you see ExpandoObject class?

您看到ExpandoObject类了吗?

Directly from MSDN description: "Represents an object whose members can be dynamically added and removed at run time."

直接从MSDN描述:“表示一个对象，其成员可以在运行时动态添加和删除。”

With it you can write code like this:

你可以这样写代码:

dynamic employee = new ExpandoObject();
employee.Name = "John Smith";
((IDictionary<String, Object>)employee).Remove("Name");

#6

Thought this might help someone in the future.

认为这对未来的人有帮助。

If you know the property name already, you can do something like the following:

如果您已经知道了属性名称，您可以做如下操作:

[HttpPost]
[Route("myRoute")]
public object SomeApiControllerMethod([FromBody] dynamic args){
   var stringValue = args.MyPropertyName.ToString();
   //do something with the string value.  If this is an int, we can int.Parse it, or if it's a string, we can just use it directly.
   //some more code here....
   return stringValue;
}

#7

IF d was created by Newtonsoft you can use this to read property names and values:

如果d是由Newtonsoft创建的，您可以使用它来读取属性名和值:

    foreach (JProperty property in d)
    {
        DoSomething(property.Name, property.Value);
    }

#8

C# - How to get Property Name and Value of a dynamic object? C# - Dynamic Object

c# -如何获取动态对象的属性名和值?c# -动态对象

Use the following code to get Name and Value of a dynamic object's property.

使用以下代码获取动态对象属性的名称和值。

dynamic d = new { Property1= "Value1", Property2= "Value2"};

var properties = d.GetType().GetProperties();
foreach (var property in properties)
{
    var PropertyName=property.Name; 
//You get "Property1" as a result

  var PropetyValue=d.GetType().GetProperty(property.Name).GetValue(d, null); 
//You get "Value1" as a result

// you can use the PropertyName and Value here
 }

#1