如何使用反射将 PropertyInfo 转换为自己的类型

Question

I am trying to use reflection for getting the property name declared and its value, I am able to get the declared property name using property info the main concern I am having is I want to get the value for the property and I don't know the object type so I cant cast directly.

I know we need to use item.GetValue(object) but here the object, I need to pass using reflection.

For example, if you see the below code

Class structure

public abstract class ObjectInputs{}

public class ValveInputs : ObjectInputs
{
    public Conditions Conditions { get; set; } = new Conditions();
}

public class Conditions :IExportable
{

    [CanExportAttribute]
    public string north {get;set;}    
}

Method

public void Append(Scenario scenario)
{
    var scenarioInputs = (commonDomain.ObjectInputs)scenario.Inputs; //  ObjectInputs is an abstract class

    var exportableInputs = scenarioInputs.GetType().GetProperties().Where(x =\> typeof(IExportable).IsAssignableFrom(x.PropertyType)); // I extraced property having interface IExportable

    var listOfExportableProperties = new ScenarioExtract();

    foreach (var exportableInput in exportableInputs)
    {
        var allProperties = ((System.Reflection.TypeInfo)exportableInput.PropertyType).DeclaredProperties; // Got all the property details

        var propertyHavingAttribute = allProperties.Where(x =\> x.CustomAttributes.Where(z =\> z.AttributeType == typeof(CanExportAttribute)).Any()).ToArray(); // Got the properties which i need to extract.

The issue is here, if i do this then its creating a new instance and the values of each properties are set to default. I want to cast the exportableInput to its type (I cant hard code the type casting) so that i can use the value below.

        object destination = Activator.CreateInstance(scenarioInputs.GetType()); 

        foreach (var item in propertyHavingAttribute)
        {
            var detail = new InputPropertyDetail { InputName = item.Name, InputValue = \*\*item.GetValue(destination).ToString() \*\*};  \*\*want to use value here\*\*

            listOfExportableProperties.PropertyDetails.Add(detail);
        }
    }

    spreadsheetBuilder.AppendComponenet(listOfExportableProperties);
}

---

Answer 1

If you're using Activator.CreateInstance, it will always create a new instance (as the name inplies) with default values. Instead you must use the value of the exportableInput property.

object destination = exportableInput.GetValue(scenarioInputs);

Then you can get the actual value of the exportable property of the instance with InputValue = item.GetValue(destination).ToString() .