问题
I am trying to figure out what I could be doing wrong in this sample project. I am getting an error when my net462
application references a netstandard1.5
library. The application has a dependency on "System.Collections.Immutable": "1.3.0"
, which targets NetStandard 1.0 according to Nuget. The library depends on "NETStandard.Library": "1.6.0"
.
Am I setting up either of these projects wrong? I would greatly appreciate any insight on this...
Here are their project.json :
app:
{
"buildOptions": {
"emitEntryPoint": true
},
"dependencies": {
"SomeLibrary": "1.0.0-*"
},
"frameworks": {
"net462": {
"dependencies": {
"System.Collections.Immutable": "1.3.0"
}
}
},
"version": "1.0.0-*"
}
Library
{
"buildOptions": {
"allowUnsafe": true
},
"dependencies": {
},
"frameworks": {
"netstandard1.5": {
"dependencies": {
"NETStandard.Library": "1.6.0"
}
}
},
"version": "1.0.0-*"
}
All the library has is this interface:
using System.Collections.Generic;
namespace SomeLibrary
{
public interface SomeInterface
{
int GetValue(KeyValuePair<string, int> somePair);
}
}
The app implements this interface and makes a call the concrete class:
public class Program
{
public static void Main(string[] args)
{
var concreteObject = new ConcreteImplementation();
var answer = concreteObject.GetValue(new KeyValuePair<string, int>("key", 33));
Console.WriteLine(answer);
}
}
class ConcreteImplementation : SomeInterface
{
public int GetValue(KeyValuePair<string, int> somePair)
{
return somePair.Value;
}
}
If I try to run the app, here is the error that I get:
{"Could not load file or assembly 'System.Runtime, Version=4.1.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The system cannot find the file specified.":"System.Runtime, Version=4.1.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a"}
Stack: at ErrorExample.Consumer..ctor()
at ErrorExample.Program.Main(String[] args) in ..\ErrorExample\src\ErrorExample\Program.cs:line 11
What am I missing here? Thanks!
回答1:
I'm not quite sure about why this is happening, but using netstandard1.4
as a TFM for your library project would resolve your issue. In other words, project.json
of your library should look like that:
{
"buildOptions": {
"allowUnsafe": true
},
"dependencies": {
},
"frameworks": {
"netstandard1.4": { // <-- replace "netstandard1.5" with "netstandard1.4" or lower
"dependencies": {
"NETStandard.Library": "1.6.0"
}
}
},
"version": "1.0.0-*"
}
And as a current general rule of thumb: avoid using netstandard1.5
and netstandard1.6
: use netstandard1.4
and lower according to your requirements until you are explicitly forced to. Wait for release of netstandard2.0
. You may read the details about it in the MSDN blog artible about .NET Standard. And here's a FAQ.
来源:https://stackoverflow.com/questions/40856177/could-not-load-file-or-assembly-error-when-net462-app-references-a-netstandard