Let's say I have multiple projects within a solution. I have the main project parent_project and another project child_project.
How can I access classes / namespaces residing in parent_project from child_project ?
I have already added a Reference to child_project in parent_project so I can't add a Reference to parent_parent in child_project as it would create a circular dependency.
Is this possible?
If you're sharing logic between projects, you need to isolate that dependency and move it to a shared location (new project for example), restructure your dependencies so that your core logic lives in a core domain-like project or mash your projects together.
The latter is not really the cleanest of solutions. I would recommend thinking about your own question and really try to answer "Why do I NEED a circular reference? How can I restructure so that my dependencies make sense?".
You can inject your dependency using an interface defined in the child project (this can be useful where major refactoring is not possible/too expensive).
e.g. In the child project:
interface IA {
DoLogicInB();
}
In the parent project:
class ConcreteA : ChildProject.IA
{
DoLogicInB() { ... }
}
In the child project, where you need the logic:
class ChildB {
void DoSomethingWithParent(IA logicEngine) {
logicEngine.DoLogicInB();
}
}
You need to then be able to inject a concrete implementation of the parent object from outside the child project.
FYI
I ended up just copying the logic to a shared location, and "child" projects can access this version. I know from a maintainability point of view this isn't the best solution but it seemed like the best compromise..
I didn't require entire namespace, but just reading some data dictionary or calling one particular method from parent project class. Here is how we got it working.
using System;
using NUnit.Framework;
using System.Collections.Concurrent;
namespace MyProject.tests
{
public class ParentChildTest
{
[Test]
public void dataAndMethodTest()
{
// add the data in parent project
Parent.propertyCache["a"] = "b";
// read the data in child project
Console.WriteLine("Read from child: " + Child.getProperty("a"));
// use Child project to call method of parent project
Console.WriteLine("Call from child: Populate method in parent: " + Child.populate("c"));
}
}
class Parent
{
// data is in Child project. Parent project just has the reference.
public static ConcurrentDictionary<string, string> propertyCache = Child.getPropertyCache();
public static string populate(string key)
{
//calculation
string value = key + key;
propertyCache[key] = value;
return value;
}
// Pass the parent project method reference to child project
public static int dummy = Child.setPopulateMethod(populate);
}
class Child
{
// data store
static ConcurrentDictionary<string, string> propertyCache = new ConcurrentDictionary<string, string>();
public static ConcurrentDictionary<string, string> getPropertyCache()
{
return propertyCache;
}
public static string getProperty(string key)
{
if (propertyCache.ContainsKey(key))
{
return propertyCache[key];
}
return null;
}
// reference to parent project method
static Func<string, string> populateMethodReference = null;
public static int setPopulateMethod(Func<string, string> methodReference)
{
populateMethodReference = methodReference;
return 0;
}
public static string populate(string key)
{
return populateMethodReference(key);
}
}
}
Read from child: b
Call from child: Populate method in parent: cc
I have to say that Yannicks answer is the way to go there normally. In your special situation (as outlined in your comment to his answer) it sounds like that would be problematic. A different way would be (only possible if the mainclass compiles into a dll):
This is one possible other route BUT has quite a few pitfalls as reflection has troubles of its own.
Ok so let's say you have a Project with 2 solution in it S1 and S2 and you have reference S1 in S2, inside S1 it you have a class P and in S2 you have three Class defined by user A B an C. now make A inherit P so when you invoke constructor of A it will invoke constructor of P (that's in In S1) noe inside P's Constructor if you want the list of all the class declared in S2 use this code.
Assembly assembly = this.GetType().Assembly;
// DefinedTypes will list all Userdefined class
foreach (var typeInfo
inassembly.DefinedTypes )
{
// typeInfo.FullName //you will have A B and C
}
© 2022 - 2024 — McMap. All rights reserved.