In C# I have a class object defined like:
public class Row
{
public string id { get; set; }
public string full_name { get; set; }
public string email { get; set; }
}
Next I can use it like:
Row row = new Row();
And then do something like this to set a value:
row.id = "id123";
How do I make some type of "dynamic" reference? This doesn't work:
string col = "id";
row[col] = "id123";
You can use Reflection in C# like this:
var prop=row.GetType().GetProperty("id");
prop.SetValue(row,"id123");
To answer your exact question, you could create a custom indexer:
public object this[string key]
{
get
{
switch(key)
{
case nameof(id): return id;
case nameof(full_name): return full_name;
case nameof(email): return email;
default: throw new ArgumentOutOfRangeException();
}
}
set
{
switch(key)
{
case nameof(id):
id = value.ToString();
break;
case nameof(full_name):
full_name = value.ToString();
break;
case nameof(email):
email = value.ToString();
break;
default: throw new ArgumentOutOfRangeException();
}
}
}
public void Foo()
{
var row = new Row();
row["id"] = "Foo";
}
Or you use reflection as TSungur has answered:
public object this[string key]
{
get
{
var prop = GetType().GetProperty(key);
return prop.GetValue(this);
}
set
{
var prop = GetType().GetProperty(key);
prop.SetValue(this, value);
}
}
However, If I were you, I would review your current library design. Probably you want to use an ORM like Entity Framework, which does all the mapping for you.
C# is a strongly typed language. This means that once a type is defined, you can't changed it dynamically during run time*. You also can't access the properties of an object with [] like in JavaScript. Therefore you can't achieve what you are looking for in C#. C# way would most likely be to access the id property directly through row.id = "id23";. In C# you always know during compile time what properties and methods are available on an object. If you need more flexibility what properties will be there, you can also use a Dictionary, KeyValuePair or simply a List.
*There is actually a dynamic key word that gives you some of that functionality - but it's uncommon to use that all over the place. Coming from JavaScript I would recommend to forget about it for the moment. There is almost always an other, "more C#-like" way.
Dictionary<string, whatever>for example..Nameand.PropertyTypeof the definition in a foreach loop. Very open to other ways; just stuck with something simple here...