The type 'MySqlConnection' exists in both 'MySql.Data Issue

Question

I have Referenced MySql.Data on one project and Other project referenced nuget package which also referenced MySqlConnector inside of it. projects has dependency .

when i compile application im getting this error

This is application hierarchy

is there any way to avoid this? or did i do anything wrong when referencing packages?

Thanks

UPDATE this is the same namespaces from difference libs

UPDATE 2

This is the sample repo which reproduced same issue

Either use the fully qualified type name, or a ```using``` qualifier at the head of the cs file to disambiguate. — Matt, Feb 08 '18 at 10:30
@Matt thanks. problem is both have same namespaces please have a look i have updated post. — Gayan, Feb 08 '18 at 10:36
Well then how is the compiler meant to know which one to use? — Christopher Lake, Feb 08 '18 at 10:50
If you google "c# type exists in both assemblies" - you will find a lot of questions about the same issue. If nothing from those questions help - please include what you tried in question. — Evk, Feb 08 '18 at 10:54
Actually `MySqlConnector` is referenced inside `Identity.Dapper.MySql` i have no way to avoid installing it — Gayan, Feb 08 '18 at 10:57
Did you try closing the solution, deleting .suo file and reopening the solution and building? — FaizanHussainRabbani, Feb 08 '18 at 11:33
@Gayan can you use same version for both of these assemblies, it might be due conflict of different versions? — FaizanHussainRabbani, Feb 08 '18 at 12:10
@FaizanRabbani that's not possible because `MySqlConnector` is in `Identity.Dapper.MySql` nuget and other one inside `MySql.Data` nuget — Gayan, Feb 08 '18 at 12:23
@Gayan then maybe you will have to place settings in config file for range of versions for both of these assemblies? — FaizanHussainRabbani, Feb 08 '18 at 12:25
No luck i believe i this documentation has something related to my problem but don't know how exactly it is https://learn.microsoft.com/en-us/nuget/consume-packages/package-references-in-project-files — Gayan, Feb 08 '18 at 13:03

score 16 · Accepted Answer · answered Feb 08 '18 at 13:37

16

In NET.Framework projects you can go to the reference properties and set an alias for assembly. Net core projects doesn't fully support yet aliases for assemblies. But there is a workaround to use aliases in .net core. Edit your csproj file like this:

<Project Sdk="Microsoft.NET.Sdk.Web">
...

  <Target Name="ChangeAliasesOfStrongNameAssemblies" BeforeTargets="FindReferenceAssembliesForReferences;ResolveReferences">
    <ItemGroup>
      <ReferencePath Condition="'%(FileName)' == 'MySqlConnector'">
        <Aliases>MySqlConnectorAlias</Aliases>
      </ReferencePath>
    </ItemGroup>
  </Target>
...
</Project>

then in your cs file before all usings:

extern alias MySqlConnectorAlias;

then you can reference to you type from MySqlConnector like this:

MySqlConnectorAlias::MySql.Data.MySqlClient.MySqlConnection

answered Feb 08 '18 at 13:37

AlbertK

11,841
5
40
36

Hi Albertk, I am trying to use your suggestion in my code as: `MySqlConnectorAlias::MySql.Data.MySqlClient.MySqlConnection mysql = new MySqlConnectorAlias::MySql.Data.MySqlClient.MySqlConnection();`and then get the error `Cannot resolve symbole MySql`. MySql.Data.MySqlClient are all read in my case. Can you please help? Thanks – Ben Aug 17 '19 at 12:38
It is hard to say for sure. Are you using Resharper? If yes then try to follow answers given here: [1](https://stackoverflow.com/questions/35227523/resharper-cannot-resolve-symbol), [2](https://stackoverflow.com/questions/2678779/why-do-i-get-an-error-cannot-resolve-symbol-symbolname-in-resharper), [3](https://stackoverflow.com/questions/48654852/resharper-cannot-resolve-symbol-when-the-code-well-compiled) – AlbertK Aug 17 '19 at 17:08

score 1 · Answer 2 · answered Nov 13 '19 at 06:12

1

It will work If you remove mysql.data reference from Your project/references.

Hope it will work for you. for me it was worked. My project is ASP.NET Core Framework. Created project in VS2017 and opening in VS2019 at that time it introduced.

answered Nov 13 '19 at 06:12

hardik patel

221
4
8

The type 'MySqlConnection' exists in both 'MySql.Data Issue

2 Answers2

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