I have an array of such object:
object[] internationalRates = new object[]
{
new { name = "London", value = 1 },
new { name = "New York", value = 2 } ,
etc...
};
I need to get List<string> of countries (or Dictionary<int, string> of pairs). How can I cast it?
You can use the dynamic keyword in this case:
var result = internationalRates.ToDictionary(
x => ((dynamic)x).value,
x => ((dynamic)x).name);
This produces a Dictionary with key/value pairs.
Warning:
The key and value are both of type dynamic, which I sorta don't like. It could potentially lead to run-time exceptions if you don't pay attention to the original types.
For example, this works fine:
string name = result[2]; // name == "New York"
This will also compile just fine, but will throw a run-time exception:
int name = result[2]; // tries to convert string to int, doesn't work
If you don't want to use dynamic you can write your own implementation of ToDictionary method with use of Reflection. Something like this :
public static class Helper
{
public static Dictionary<T1, T2> ToDictionary<T1, T2>(this IEnumerable<object> dict, string key, string value)
{
Dictionary<T1, T2> meowDict = new Dictionary<T1, T2>();
foreach (object item in dict)
meowDict.Add((T1)item.GetType().GetProperty(key).GetValue(item),
(T2)item.GetType().GetProperty(value).GetValue(item));
return meowDict;
}
}
Usage example :
object[] internationalRates = new object[]
{
new { name = "London", value = 1 },
new { name = "New York", value = 2 } ,
};
var dict = internationalRates.ToDictionary<int, string>("value", "name");
foreach (KeyValuePair<int, string> item in dict)
Console.WriteLine(item.Key + " " + item.Value);
Console.ReadLine();
Output :
1 London
2 New York
Change your definition to this:
var internationalRates = new []
{
new { name = "London", value = 1 },
new { name = "New York", value = 2 } ,
};
And then you can use this:
var res = internationalRates.ToDictionary(x => x.value, x => x.name);
