Can't find System.Data

Questions & Answers
1

Hello.
I’m using Unity 5.0.1f1 (64-bit) for windows and i’ve been trying to connect to DB so i should use packae System.Data. But when i’m typeing using System.Data; i’m getting an error :

Error CS0234: The type or namespace name ‘Data’ does not exist in the namespace ‘System’ (are you missing an assembly reference?) (CS0234) (Assembly-CSharp)

So it’s seems to me that my unity doesn’t have package System.Data. The question is : Where i can get it and how i can install it?

Thanks.

2

Hi you have to add the .dll file of System.Data to your Assets\Plugins folder . To do so, go to your directory Unity\Editor\Data\Mono\lib\mono\2.0 and get the System.Data file and later add it to the folder mention before.

3

If you have .NET installed already, you can copy the dll from there and paste into your project “Assets\Plugins”.

Depending on which version you want, you can find the dll
C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework.NETFramework
or
C:\Program Files (x86)\Unity\Editor\Data\MonoBleedingEdge\lib\mono\2.0

If not, or still having trouble locating it. Do a search for “System.Data.dll” from C:\

4

Hi,
I have followed the instructions here (and in various other posts) and it all seems to make sense.
I have no issues at compile time or in Unity itself except that when I try to run the project I get a nice big message saying that “All compiler errors must be fixed before you can enter play mode”. Well There are no compiler errors!

I have take System.Data.dll from C:\Program Files\Unity\Editor\Data\MonoBleedingEdge\lib\mono\2.0

The error seems to manifest as soon as I try to instantiate a SqlConnection object. I can create a variable reference to it no problem, but cannot instantiate it.

I can however create objects in System.Data.SqlClient no problem.

Any More ideas please

5

I have done all this and it still will not find System.Data.dll in the C sharp scripts.
I copied the C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework.NETFramework version into Assets/Plugins as per the instructions.
running MS visual Studio community 2015 and Unity 5.6.0f3(64bit)
Any suggestions as to where I am going wrong.

6

You can show this videos to connect unity 3d and sqlite and solved all dll error compile for different windows 32bit and 64bit

7

I was facing same issue and this can be 2 issues.

I already had the system.data dll in plugins.

BUT it was not being referenced BECAUSE that dll targets .net3.5 and I was building targeting 4.X

Switch to 3.5, restart Unity, relaunch VS and tadaaa.