I've created a program with some very big .cs files. So i tried to split one of them up by using partial classes. So i created a second file with same class name inside and same namespace.
I cut some functions from one file and pasted it in the second one. But when i want to run the program it says that the class already exists. But its a partial class it has to have the same name :S
At the first file (ChartWidget.cs) it starts with:
namespace UGS.Sidebar.ChartWidget
{
public partial class ChartWidget : UserControl
{
#region declarations
private int id = -1;
.....
At the second file (Debugging.cs) it starts with:
namespace UGS.Sidebar.ChartWidget
{
public partial class ChartWidget : UserControl
{
#region debugvars
Random _r = new Random();
#endregion
.....
those files are from an Usercontrol (as you can see) but i dont think that this is the problem?
Hope you guys can tell me why it doesnt work :(
And sorry for my bad english i really suck ... :)
Check you haven't appended the class name on to the end of a namespace. e.g. if you put your new class into a folder of the same name, it will automatically get suffixed on the namespace name
No need to inherit from UserControl in second class
Check if somewhere else the class is defined without the partial. Right click on the class name + Find All Reference could help.
Related
It was taught to me that any alterations to an object on a form (change the text, make visible/invisible or change the color and so on) should be done in the corresponding form class.
But due to the large amount of such alterations done inside the project, the file has became large and hard to search through. I've read online that a Partial Class could help, but there was no explanation on how to implement this. As an easy example, I have the following 2 files:
Form_Main.cs
namespace Test
{
partial class Form_Main : Form
{
public Form_Main()
{
InitializeComponent();
}
}
}
AND Form_Main.Dataloader.cs
namespace Test
{
partial class Form_Main : DataLoader
{
public void SetText()
{
TextBox_StudentSurname.Text = "1";
}
}
}
How can I make this work? Because if I do this I get several errors in the designer.
Your main problem is the first error printed: You cannot declare different base classes in different partial implementations. I don't know which of the two base classes is the right one (the one you previously used), but as always, a class cannot have two base classes. It is legal to specify the base class only in one of the parts, but if it is specified multiple times, it must be the same.
I'm creating static partial class like this.
If I put them in the same file there is no problem, but when I move one class to another file in the same project, this method private_method_from_a() does not exist anymore.
Is this by design? Do I miss something here?
//File A
public static partial class PartialClass
{
private static void private_method_from_a()
{
//Do something
}
}
//File B
public static partial class PartialClass
{
public static void public_method_b()
{
private_method_from_a();
}
}
Most likely the two files are in different namespaces, as #MickyD suggested in a comment. The reason for this problem is you're then making 2 different classes entirely. Chances are, one of them is in the namespace of your project, while the other is in the global namespace - that is, you didn't specify a namespace for it at all. Here's how the compiler sees them (suppose your project is called "MyProject", and has that name as the top-level namespace):
partial class global::MyProject.PartialClass
and
partial class global::PartialClass
Well, that's two distinct types, with different fully qualified names, both partial.
Make sure they're are both in the same namespace for the C# compiler to treat them as the same type.
I'm a student learning mainly C++, but this term we have to code our math assignments using C#.
Our professor supplied a basic skeleton program but I'm not very good at C#. He gave us two class files (.cs) but when I add them to my project, I'm unable to utilize them at all. I can't create a class object from either class.
The classes are just Line3d and Point3d. They have the variables needed to compute points and collision.
Thanks for any advice.
Compile your project.
Use Ctrl + . or bulb icon (type your class name you want to use and locate your cursor position over that class name) to resolve namespace for these classes or write using directive manually.
C# classes are normally encapsulated in namespaces. In Visual Studio, adding a new class will generate a file containing a namespace similar to PROJECT_NAME.SUBFOLDER.SUBSUBFOLDER For example:
// MyClass.cs
using System;
namespace MyProject
{
public class MyClass
{
}
}
And then you can reference that from another class in the same namespace, but you can't reference it from a class in another namespace (unless it's a namespace that starts with MyProject.).
// Line3d.cs
using System;
namespace TemplateProject
{
public class Line3d
{
}
}
// MyClass.cs
using System;
namespace MyProject
{
public class MyClass
{
public Line3d LineInstance {get;set;}
}
}
In this example, it won't work because the compiler doesn't know which namespace Line3d exists in (and, indeed, two class with the exact same name could exist in two different namespaces). You need to instruct the compiler to include classes from the TemplateProject namespace (note this doesn't include classes in the TemplateProject.ChildNamespace namespace):
// MyClass.cs
using System;
using TemplateProject;
namespace MyProject
{
public class MyClass
{
public Line3d LineInstance {get;set;}
}
}
Now you should be able to find the Line3d class and use it.
Besides manually referencing the namespace, you can also right-click an unknown class reference, select "Quick actions and Refactorings...", and then you will see something like "using TemplateProject;". Click on this and it will automatically add the using for you.
You can also use the Ctrl+. keyboard shortcut, which does the same as right-click/Quick actions, if you don't want to use the mouse.
select your project and press [ Shift + Alt + A ] to add existing files.
you can see dialog form that allows to open cs file on project.
After that, you can use professor's class files.
I have a class Employee.cs that was autogenerated by EntityFramework when i connected to a database, now i want to implement a partial class but I can't use "Employee.cs" name for that class because it already exists. Can I give other name to it and it will work? Can you explain how the compiler will know that there is another partial class of Employee.cs?
You can give the file whatever name you want like Employee.custom.cs but you have to call the class in it Employee in the same namespace as the Employee class in the other file, also with a partial modifier, and you should be good to go.
The compiler just gathers all the partial classes with the same name and compiles it into one class per name.
Compiler always works with fullname of class. If there is a project named MyProject, full name for the class would be something like:
MyProject.Employee
If You want to create class with the same name, You have to add a level of separation in naming, or if it have to be partial class with this generated class, You have to mark it also as a partial.
You can either create (in Model/Employee.cs):
public class MyProject.AnySubPath.Employee {}
Or:
In file Model/Employee.cs
public partial class MyProject.Employee {}
In file ViewModel/Employee.cs
public partial class MyProject.Employee {}
Important for You is to realize what is the partial mean & what will the compiler to with Your class: In fact the compiler will just put all the partial classes together and then compile them. Only benefit from being partial is that You can have the code split among multiple files. Excelent example for this is Windows.Forms, where You have "code-behind" file (Form1.cs) and then You have "designer" file (Form1.Designer.cs).
Also You can name the files whatever name You want, it is just common standard to have 1 class = 1 file and the class name should fit the file name.
How do I declare a textbox in the XAML code that is used in a class? I copied all the source code from the MainWindow.xaml.cs to another class because the MainWindow is getting to big.
I hope you can help me. Thanks in advance.
The following causes the error:
TextChanged="textBox_1_Kurzbeschreibung_TextChanged"
EDIT: The following statement solved the problem.
~closed.
Simple make the class partial, and then use the same name in the two classes.
public partial class MyClass
{
// code....
}
The other class need to be equal:
public partial class MyClass
{
// code....
}
From MSDN:
"Partial type definitions allow for the definition of a class, struct, or interface to be split into multiple files
See more here: http://msdn.microsoft.com/en-us/library/wbx7zzdd.aspx