How to find a specific value in an IDictionary?

Question

This IDictionary<string, object> contains user data I'm logging into mongodb. The issue is the TValue is a complex object. The TKey is simply the class name.

For example:

public class UserData
{
    public string FirstName { get; set; }
    public string LastName  { get; set; }
    public Admin NewAdmin   { get; set; }
}    
public class Admin
{
    public string UserName { get; set; }
    public string Password { get; set; }
}

Currently, I'm trying to iterate through the Dictionary and compare types but to no avail. Is there a better way of doing this or am I missing the mark?

var argList = new List<object>();
foreach(KeyValuePair<string, object> kvp in context.ActionArguments)
{
    dynamic v = kvp.Value;
    //..compare types...
}

"Better way of doing this..." Better way of doing what, exactly? You described your solution but not your problem. — John Wu, Aug 22 '18 at 20:50
Are you guaranteeing that the key (class name) means that there is only ever one of each type of class in the collection? I'm not sure what you are trying to do here... — Ron Beyer, Aug 22 '18 at 20:50

John Wu · Accepted Answer · 2018-08-22T21:21:06.483

Just use OfType<>(). You don't even need the key.

public static void Main()
{
    var d = new Dictionary<string,object>
    {
        { "string", "Foo" },
        { "int", 123 },
        { "MyComplexType", new MyComplexType { Text = "Bar" } }
    };

    var s = d.Values.OfType<string>().Single();
    var i = d.Values.OfType<int>().Single();
    var o = d.Values.OfType<MyComplexType>().Single();

    Console.WriteLine(s);
    Console.WriteLine(i);
    Console.WriteLine(o.Text);
}

Output:

Foo
123
Bar

Link to Fiddle

How to find a specific value in an IDictionary?

1 Answers1