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C# There is no argument given that corresponds to the required

I am receiving an error: There is no argument given that corresponds to the required formal parameter 'x' of ReadingMaterial.By(string). I'm looking for a little guidance as to why there is an error. Is my syntax wrong, or is there something else I'm missing? I have been trying to learn C# by using some online tutorials and trying to change them up a bit.
namespace ReadingMaterials
{
class Presentation
{
static void Main(string[] args)
{
aForm Form = new aForm(); // available in hardcopy form aForm.availForm
Online O = new Online(); // amtBlogs, amtBooks
Book B = new Book(); // hardCover, softCover
Magazine M = new Magazine(); // numArticles
O.blog(5); //contains 5 blogs
O.oBook(3); //contains 3 online books
O.By("Beck"); //Written by Beck
O.words(678); //with 678 combined words
O.pics(1); // with one pic
Console.WriteLine("The auther {0} ", O.By());
Form.availForm();
B.hardCover(10); //10 hardcover books
B.softCover(2); //2 softcover books
B.By("Bruce"); //Writen by Bruce
B.words(188264); //words combined
B.pics(15); //15 pictures
Form.availForm();
M.articles(5); //5 articles
M.By("Manddi"); //Writen by Manddi
M.words(18064);//combined words
M.pics(81); //81 pictures
Form.availForm();
}
}
class ReadingMaterial
{
protected int amtWords;
string author;
protected int pic;
public void words(int w)
{
amtWords = w;
}
public void By(string x)
{
author = x;
}
public void pics(int pi)
{
pic = pi;
}
}
class Online : ReadingMaterial
{
int amtBlogs;
int amtBooks;
public void blog(int s)
{
amtBlogs = s;
}
public void oBook(int b)
{
amtBooks = b;
}
}
class Book : ReadingMaterial
{
int hard;
int soft;
public void hardCover(int h)
{
hard = h;
}
public void softCover(int s)
{
soft = s;
}
}
class Magazine:ReadingMaterial
{
int numArticles;
public void articles(int a)
{
numArticles = a;
}
}
interface IPrintable
{
void availForm();
}
class aForm : IPrintable
{
public void availForm ()
{
Console.WriteLine("Available in hard copy form!");
}
}
}

Console.WriteLine("The auther {0} ", O.By()); is the culprit. O.By() expects a string, and the By() function sets the author, but doesn't return any string. Since you've set the author using the By() function, you can make the author a public field, and do Console.WriteLine("The auther {0} ", O.author);

The problem is that you are calling By without any parameters in this line:
Console.WriteLine("The auther {0} ", O.By());
You can add a method to get the value instead:
class ReadingMaterial
{
...
public string GetBy()
{
return author;
}
....
}
Anyways, you might want to use properties instead of functions. You can look at the code working in here
class ReadingMaterial
{
public string Author {get;set;}
...
}
static void Main(string[] args)
{
...
O.Author = "Beck"; //Written by Beck
...
Console.WriteLine("The auther {0} ", O.Author);
}

You have defined the By method like this, with a parameter:
public void By(string x)
{
author = x;
}
But you are trying to call it without a parameter:
Console.WriteLine("The auther {0} ", O.By()); // not passing a parameter to 'By()'
If you want to access the author value of ReadingMaterial here then I would suggest making it a public property rather than a private field:
class ReadingMaterial
{
protected int amtWords;
public string Author { get; private set;}
// skipped
public void By(string x)
{
Author = x;
}
All of which kinds of begs the question - why use methods to set the values at all? Why not just use properties, as suggested below by #CarlosGarcia?

C# Visual Studio 2015 bug?

I'm playing with VS. I'm a rookie, It must be basic. I have created 2 classes and I puzzled with result. I'm using Visual Studio 2015 community edition.
I'm expect to receive at console :
myfirstClass
Class
first.
mysecondClass
Class
second.
I received :
myfirstClass
Class
_
class Program
{
public class mysecondClass
{
static public string myName ;
public mysecondClass()
{
Console.WriteLine("mysecondClass");
myName = "Class";
}
public static void Display()
{
Console.WriteLine(myName);
}
~mysecondClass()
{
Console.WriteLine("second.");
}
}
public class myfirstClass
{
public string myName;
public myfirstClass()
{
Console.WriteLine("myfirstClass");
myName = "Class";
}
public static void Display()
{
myfirstClass d = new Program.myfirstClass();
Console.WriteLine(d.myName);
}
~myfirstClass()
{
Console.WriteLine("first.");
}
}
static void Main(string[] args)
{
myfirstClass.Display();
mysecondClass.Display();
Console.ReadLine();
}
}

This is not a bug in Visual Studio. I think you have got two concepts wrongly.
Firstly, the finaliser of a class will not be called immediately after the object is out of scope. It will be called at a random time. It is quite unpredictable.
Therefore, this:
Console.WriteLine("first.");
is not printed.
The second thing is that constructors of a class is only called when you write new XXX(...) (or through reflection). Just calling a static method will not invoke the constructor.
In other words, these lines are never executed:
Console.WriteLine("mysecondClass");
myName = "Class";
You never wrote new mysecondClass().
When this line in the display method of mysecondClass executes:
Console.WriteLine(myName);
Since myName has not been assigned, it is null, and so nothing is printed.

class Program
{
public class mysecondClass
{
public string myName { get; set; }
public mysecondClass()
{
Console.WriteLine("mysecondClass");
myName = "Class";
}
public static void Display()
{
var mySecond = new mysecondClass();
Console.WriteLine(mySecond.myName);
}
~mysecondClass()
{
Console.WriteLine("second.");
}
}
public class myfirstClass
{
public string myName { get; set; }
public myfirstClass()
{
Console.WriteLine("myfirstClass");
myName = "Class";
}
public static void Display()
{
myfirstClass d = new myfirstClass();
Console.WriteLine(d.myName);
}
~myfirstClass()
{
Console.WriteLine("first.");
}
}
static void Main(string[] args)
{
myfirstClass.Display();
mysecondClass.Display();
Console.ReadLine();
}
}
try this

Program does not contain a static 'main' method suitable for an entry point : i have tries even removing access modifier before static

using System;
namespace inheritance1
{
public class Employee
{
public string FirstName;
public string LastName;
public string Email;
public void PrintFullName()
{
Console.WriteLine(FirstName + " " + LastName);
}
}
public class FullTimeEmployee : Employee
{
public float YearlySalary;
}
public class PartTimeEmployee : Employee
{
public float HourlyRate;
}
public class Program
{
public static void main(String[] args)
{
FullTimeEmployee FTE = new FullTimeEmployee();
FTE.FirstName = "Max";
FTE.LastName = "Striker";
FTE.YearlySalary = 500000;
FTE.PrintFullName();
PartTimeEmployee PTE = new PartTimeEmployee();
PTE.FirstName = "king";
PTE.LastName = "Maker";
PTE.HourlyRate = 500;
PTE.PrintFullName();
}
}
}

It is Main with an upper case M, not main.
public static void Main(String[] args)
{
Main () and Other Methods (C# vs Java)
Every C# application must contain a single Main method specifying
where program execution is to begin. In C#, Main is capitalized,
while Java uses lowercase main.

Can I bypass Console.ReadKey() issue when input is redirected?

I am a C# teacher and I wrote some automated HW checker for my students.
The students write C# Console Applications. My HW checker is based on input redirection so I can test their code on my own generated input.
The problem is that students sometimes end their program with a Console.ReadKey() instruction (They do so just to make the execution window not close when they ran the program under F5 - Debug). The Console.ReadKey() crashes when ran under input redirection with the following exception:
System.InvalidOperationException: Cannot read keys when either application does not have a console or when console input has been redirected from a file.
Do I have any way to "bypass" this problem (without altering the students code)? Maybe tell Console to ignore ReadKey instructions?

I see a clear case for a Dependency Injection pattern.
Let's build a simple example, with Read, ReadLine and WriteLine functionalities polymorphically: your students must write a homework in which a number given in the Console.ReadLine() must be parsed as int and returned to the Console Window.
Usually a student writes something like:
class Program
{
static void Main(string[] args)
{
var stringValue = Console.ReadLine();
int number;
if (int.TryParse(stringValue, out number))
Console.WriteLine($"The double of {number} is {number * 2}");
else
Console.WriteLine($"Wrong input! '{stringValue}' is not an integer!");
Console.Read();
}
}
Now, instead, create an interface for the Console functionalities:
public interface IOutput
{
void Read();
string ReadLine();
void WriteLine(string text);
}
A student must create a Homework class that wraps all the required homework code, using an IOutput instance in this way:
public class HomeWork
{
private IOutput _output;
public HomeWork(IOutput output)
{
_output = output;
}
public void Run()
{
_output.WriteLine("Give me an integer:");
var stringValue = _output.ReadLine();
int number;
if (int.TryParse(stringValue, out number))
_output.WriteLine($"The double of {number} is {number * 2}");
else
_output.WriteLine($"Wrong input! '{stringValue}' is not an integer!");
_output.Read();
}
}
The Main becomes:
static void Main(string[] args)
{
var h = new HomeWork(new ConsoleOutput());
h.Run();
}
You give them also the ConsoleOutput class:
public class ConsoleOutput : IOutput
{
public void Read()
{
Console.Read();
}
public string ReadLine()
{
return Console.ReadLine();
}
public void WriteLine(string text)
{
Console.WriteLine(text);
}
}
So the use it instead of call directly Console.Read() etc.
The student must pass to you not the entire Application, but only the Homework class.
You can create a test class that use the Homework class with some test implementations of IOutput like the followings:
public abstract class TestOutput : IOutput
{
public TestOutput()
{
Outputs = new List<string>();
}
public void Read()
{
//do nothing?
}
public abstract string ReadLine();
public void WriteLine(string text)
{
Outputs.Add(text);
}
public List<string> Outputs { get; set; }
}
public class TestOutputWithAValidNumber : TestOutput
{
public TestOutputWithAValidNumber(int value)
{
Value = value;
}
public override string ReadLine()
{
return Value.ToString();
}
public int Value { get; }
}
public class TestOutputWithNotValidNumber : TestOutput
{
public TestOutputWithNotValidNumber(string value)
{
Value = value;
}
public override string ReadLine()
{
return Value;
}
public string Value { get; }
}
The test class can be something like this:
[TestClass]
public class TestOutputClass
{
[TestMethod]
public void TestGoodNumber()
{
var testOutput = new TestOutputWithAValidNumber(1234);
var h = new HomeWork(testOutput);
h.Run();
Assert.AreEqual(1234, testOutput.Value);
Assert.AreEqual("Give me an integer:", testOutput.Outputs[0]);
Assert.AreEqual("The double of 1234 is 2468", testOutput.Outputs[1]);
}
[TestMethod]
public void TestWrongNumber()
{
var testOutput = new TestOutputWithNotValidNumber("foo");
var h = new HomeWork(testOutput);
h.Run();
Assert.AreEqual("foo", testOutput.Value);
Assert.AreEqual("Give me an integer:", testOutput.Outputs[0]);
Assert.AreEqual("Wrong input! 'foo' is not an integer!", testOutput.Outputs[1]);
}
}
If you need only to wrap the Console.Read() method, feel free to simplify all this code, but IMHO I thought that a wider view on this possible solution would have been useful anyway.

If the executables are in IL, you can create an easy application that uses ILDASM.
The key point is: disassemble the executable with ILDASM into a text file/stream, look for any call to Console.Read and remove it, than recompile it and run.

Getting Object reference required for the non-static method

Please take note that this is uncompleted code, but just facing some small issue, as i using a lot of c++ OOP concept. i might have some issue when trying to change from another platform.
I get error when compiled and stated nonstatic method/property error
using System;
public class People
{
string name;
int age;
int height;
public virtual void insertDetail(People stu)
{
Console.Write("Please enter name : ");
stu.name = Console.ReadLine();
Console.Write("Please enter age : ");
while(!int.TryParse(Console.ReadLine(), out stu.age))
{
Console.WriteLine("You enter characters! Please re-insert");
}
Console.Write("Please enter height: ");
while(!int.TryParse(Console.ReadLine(), out stu.height))
{
Console.WriteLine("You enter characters! Please re-insert");
}
}
}
public class Class : People
{
static People[] students = new People[5];
public override void insertDetail(People stu)
{
Console.WriteLine("==================================");
base.insertDetail(stu);
}
public static void Main(string[] args)
{
for (int i = 0; i < students.Length; i++)
{
students[i] = new People();
insertDetail(students[i]);
}
Console.ReadKey();
}
}

As said in comments, you need an instance to use instance method.
Create an instance for Class inside Main
public class Class : People
{
static People[] students = new People[5];
public override void insertDetail(People stu)
{
Console.WriteLine("==================================");
base.insertDetail(stu);
}
public static void Main(string[] args)
{
Class c = new Class(); // this is required to access insertDetail
for (int i = 0; i < students.Length; i++)
{
students[i] = new People();
c.insertDetail(students[i]);
}
Console.ReadKey();
}
}
Check this Demo

You get that error when you make a static call to an instance method like Object.ToString() using the type name as the qualifier when you really need an instance.

First of all never use Class as your class name.
As for the error you need to give more information about what are you trying to do. You have to add static modifier to your method:
public static void insertDetail(People stu)
Or if you want for it to be override than:
public virtual void insertDetail()
{
this.name = "Some name";
//...
}