Is it possible to cast a variable of type: dictionary<int, models.user> to dictionary<int, object> in C#?

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Hi, everyone. I am working on a c# application where I have about 15 methods that Update entries in the database. So I want to make one method for update with two parameters: Dictionary<int, object> dictionary and string tableName. The 'object' part of the dictionary will accept different ViewModels. Here is my code:

C#

public void UpdateEntriesFromAGivenTable(Dictionary<int, object> dictionary, string tableName)
        {
            foreach (KeyValuePair<int, object> entry in dictionary)
            {
                Dictionary<string, object> dict = GetTypeNamesAndValuesWithReflection(entry.Value);

                foreach (var item in dict)
                {
                    if (item.Value != null && (!string.Equals(item.Key, "id")))
                    {
                        UpdateEntry(tableName, item.Key, item.Value, entry.Key);
                    }
                }
            }
        }

But when I tried to use the above method, I receive the red underline below the parameter "Dictionary<int, user>" and the error message is: cannot convert from 'System.Collections.Generic.Dictionary<int, Models.User> to 'System.Collections.Generic.Dictionary<int, object>.

What I have tried:

I tried the following cast:

(Dictionary<int, object>)(users)

but without success. I looked for help in google and stackoverflow but did not find a similar issue. So can you tell me is it possible to cast a variable of Type: Dictionary<int, Models.User> to Dictionary<int, object> and if the answer is yes, how to do it? Thanks.

Posted 27-Sep-18 1:23am

Member 13992723

Updated 27-Sep-18 2:31am

Herman<T>.Instance

v2

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2 solutions

Solution 1

See here: C# cast Dictionary<string, AnyType> to Dictionary<string, Object> (Involving Reflection) - Stack Overflow[^]

Posted 27-Sep-18 2:23am

OriginalGriff

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F-ES Sitecore · Accepted Answer · 2018-09-27T02:32:00

Use generics

public void UpdateEntriesFromAGivenTable<T>(Dictionary<int, T> dictionary, string tableName)
{
    foreach (KeyValuePair<int, T> entry in dictionary)
    {
        Dictionary<string, object> dict = GetTypeNamesAndValuesWithReflection(entry.Value);

        foreach (var item in dict)
        {
            if (item.Value != null && (!string.Equals(item.Key, "id")))
            {
                UpdateEntry(tableName, item.Key, item.Value, entry.Key);
            }
        }
    }
}

You can call it like

Dictionary<int, User> d = new Dictionary<int, User>();

d.Add(1, new User { Name = "A" });
d.Add(2, new User { Name = "B" });

UpdateEntriesFromAGivenTable(d, "");