Passing Dictionary as a parameter to a function

Question

I created my data dictionary:

Dim data As New Dictionary(Of String, String)
data.Add("customer", "TEST")
data.Add("secretKeyId", "2222222222222")
data.Add("secretKey", "333333333333333")

and I have the following function:

 Public Shared Function Create(ByVal data As Dictionary(Of String, Object)) As [String]
    ' Serializes the body into JSON using the fastJSON library.
    Dim json As String = Newtonsoft.Json.JsonConvert.SerializeObject(data)
    Dim body As Byte() = Encoding.UTF8.GetBytes(json) ....

How can I call the Create function and pass the DATA with all the keys and values that I entered to this function?

I tried: create(data.all) or create(data) but it is not working.

Please learn how to format your questions - which can be found using the [help pages](http://stackoverflow.com/editing-help) — freefaller, Apr 24 '14 at 17:48
can you expand on "its not working"; mindreading skills are at the cleaners, but why is it `Dictionary(Of String, String)` one place and `Dictionary(Of String, Object)` in the other? — Ňɏssa Pøngjǣrdenlarp, Apr 24 '14 at 17:49
I think, this is not supported based on an old answer here - http://stackoverflow.com/questions/2149589/idictionarytkey-tvalue-in-net-4-not-covariant. Has anything changed on this? — shahkalpesh, Apr 24 '14 at 18:06

score 0 · Answer 1 · answered Apr 24 '14 at 17:53

You are trying to pass an incompatible data type to your method: in your caller method your dictionary is of type string, string and your function awaits dictionary of type string, object. You have two solutions:

either change the signature of your dictionary in the main part to Dim data As New Dictionary(Of String, Object)
or change the signature to the dictionary parameter of the method to ByVal data As Dictionary(Of String, String)

A possible solution looks like this:

Public Shared Function Create(ByVal data As Dictionary(Of String, String)) As [String]
    ' Serializes the body into JSON using the fastJSON library.
    Dim json As String = Newtonsoft.Json.JsonConvert.SerializeObject(data)
    return json
end function

The call:

Dim data As New Dictionary(Of String, String)
data.Add("customer", "TEST")
data.Add("secretKeyId", "2222222222222")
data.Add("secretKey", "333333333333333")
Dim dataAsJson = Create(data)
Console.WriteLine(dataAsJson)

The output:

{"customer":"TEST","secretKeyId":"2222222222222","secretKey":"333333333333333"}

This would also work correctly in this case and create the same result as above:

Public Shared Function Create(ByVal data As Dictionary(Of String, Object)) As [String]
    ' Serializes the body into JSON using the fastJSON library.
    Dim json As String = Newtonsoft.Json.JsonConvert.SerializeObject(data)
    return json
end function

Dim data As New Dictionary(Of String, Object)
data.Add("customer", "TEST")
data.Add("secretKeyId", "2222222222222")
data.Add("secretKey", "333333333333333")
Dim dataAsJson = Create(data)
Console.WriteLine(dataAsJson)

Thanks pasty . thanks for noticing it. I wasnt even looking at that — user3570022, Apr 24 '14 at 19:02

Passing Dictionary as a parameter to a function

1 Answers1