Cannot convert type error, but both types are the same?

Question

public static Dictionary<string, User> userList = new Dictionary<string, User>();

That's how "userList" gets declared in another class. BTW the name of that class is "User" the same as the type, which could cause the problem but i am not sure. I have no idea how to make this work honestly.

Here's the full script: https://pastebin.com/h56ukpgR Some things in the script dont make sense yet because i copied some stuff from another script.

But basically i am trying to check if a nickName already exists in a static dictionary, and if so notify the user and don't do anything else.

What are the keys in the dictionary? If they're the nicknames you can lookup the key. Otherwise you can iterate all users with `foreach(User u in User.userList.Values)`. — Lee, Jan 07 '20 at 12:04

score 6 · Accepted Answer · edited Jan 13 '20 at 16:33

User.userList is a Dictionary<string, User>. If you iterate over it, each element is a KeyValuePair<string, User>, not a User.

So you can either do:

foreach (KeyValuePair<string, User> kvp in User.userList)
{
    User user = kvp.Value;
}

Or you can iterate directly over the dictionary's values:

foreach (User user in user.userList.Values)
{
}

If the key for each User in your dictionary is the user's nickname, then you don't need the loop at all. Your code:

foreach (User u in User.userList)
{
    string uN = u.GetNickName();
    if (name == uN)
    {
        builder.WithTitle("A practice with the name you specified already exists!");
        goto EndFunction;
    }
}

EndFunction:
await ReplyAsync("", false, builder.Build());

Can be replaced with:

if (User.userList.ContainsKey(name))
{
    builder.WithTitle("A practice with the name you specified already exists!");
}

await ReplyAsync("", false, builder.Build());

If not, you can still simplify this code using linq's Any:

if (User.userList.Values.Any(x => x.GetNickName() == name))
{
    builder.WithTitle("A practice with the name you specified already exists!");
}

await ReplyAsync("", false, builder.Build());

Finally, using goto in this way is not recommended. You can break out of a loop simply by using break;.

score 2 · Answer 2 · edited Jan 09 '20 at 11:40

2

For future readers, an hint to solving these kinda problems is to look at the error message. Here it says:

Cannot convert KeyValuePair<string, User> to User

That simply means the expected cast is a KeyValuePair<string, User> and not a User.

So, your code would work if you replace User In the loop with KeyValuePair<string, User>.

edited Jan 09 '20 at 11:40

canton7

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answered Jan 07 '20 at 12:37

preciousbetine

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Cannot convert type error, but both types are the same?

2 Answers2