Locating Class Property by Name from an String

Question

I want to be able to determine which class property has been selected based on a string input by the user, where the string is the name of one of the class properties.

For example

string userInput = "PropertyName";
string newValue = "some value";
MyClass c = new MyClass();
c.PropertyName = newValue;

But I do not know how to locate Properties of a custom class by Name in this way.

Can anyone suggest the most concise way of achieving this please.

You can use Reflection, but you should probably rethink the design. Maybe make an indexer instead. — Magus, Nov 12 '13 at 16:05
Users don't select class properties. Be careful not to mixup UI design decisions with code design decisions. Key Value Pairs such as a `Dictionary<>` can be used to select an item based on string input from a console. — P.Brian.Mackey, Nov 12 '13 at 16:09
@P.Brian.Mackey The exception of course are dev tools where you might want to deal with class members by name — Conrad Frix, Nov 12 '13 at 16:16

Michael Mairegger · Answer 1 · 2013-11-12T16:51:37.250

2

Use reflections:

var prop = c.GetType().GetProperty(userInput,BindingFlags.Public | BindingFlags.Instance)
if(prop != null && prop.CanWrite)
{
    prop.SetValue(c,newValue,null);
}

edited Nov 12 '13 at 16:51

answered Nov 12 '13 at 16:07

Michael Mairegger

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Thanks for that, but I am getting the compile error "No overload for SetValue takes 2 arguments". Please advise. – PJW Nov 12 '13 at 16:11
Ah, ok. This method is new in .NET 4.5. Prior that you have to use the SetValue method with 3 Parameters. I have updated the answer. – Michael Mairegger Nov 12 '13 at 16:51

score 0 · Answer 2 · answered Nov 12 '13 at 16:24

Thanks for the link to Setting a Property by Reflection

I was able to use the following to achieve my objectives

PropertyInfo propertyInfo = c.GetType().GetProperty(userInput);
propertyInfo.SetValue(c, Convert.ChangeType(newValue, propertyInfo.PropertyType), null);

Locating Class Property by Name from an String

2 Answers2