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Structs are the userdefined data type. Structs are defined by using the struct keyword in c#.
for example:
It is an error to define a default (parameterless) constructor for a struct. It is also an error to initialize an instance field in a struct body. You can initialize struct members only by using a parameterized constructor or by accessing the members individually after the struct is declared.
This example demonstrates struct initialization using both default and parameterized constructors.
Structs Almost have same syntax as classes, But structs are more limited than classes:
• Within a struct declaration, fields cannot be initialized unless they are declared as const or static.
• A struct cannot declare a default constructor (a constructor without parameters) or a destructor.
• Structs are copied on assignment. When a struct is assigned to a new variable, all the data is copied, and any modification to the new copy does not change the data for the original copy.
• Structs are value types but classes are reference types.
• structs can be instantiated without using a new operator.
• Structs can declare constructors that have parameters.
• A struct cannot support the inheritance.
• All structs inherit directly from System.ValueType, which inherits from System.Object.
• A struct can implement interfaces.
• A struct can be used as a nullable type and can be assigned a null value.
for example:
public struct StructA
{
public int x, y;
public A(int p1, int p2)
{
x = p1;
y = p2;
}
}
{
public int x, y;
public A(int p1, int p2)
{
x = p1;
y = p2;
}
}
It is an error to define a default (parameterless) constructor for a struct. It is also an error to initialize an instance field in a struct body. You can initialize struct members only by using a parameterized constructor or by accessing the members individually after the struct is declared.
This example demonstrates struct initialization using both default and parameterized constructors.
public struct StructA
{
public int x, y;
public StructA (int p1, int p2)
{
x = p1;
y = p2;
}
}
class TestStructA
{
static void Main()
{
// Initialize:
StructA StructA1 = new StructA();
StructA StructA2 = new StructA(10, 10);
// Display results:
Console.Write("StructA 1: ");
Console.WriteLine("x = {0}, y = {1}", StructA1.x, StructA1.y);
Console.Write("StructA 2: ");
Console.WriteLine("x = {0}, y = {1}", StructA2.x, StructA2.y);
// Keep the console window open in debug mode.
Console.WriteLine("Press any key to exit.");
Console.ReadKey();
}
}
{
public int x, y;
public StructA (int p1, int p2)
{
x = p1;
y = p2;
}
}
class TestStructA
{
static void Main()
{
// Initialize:
StructA StructA1 = new StructA();
StructA StructA2 = new StructA(10, 10);
// Display results:
Console.Write("StructA 1: ");
Console.WriteLine("x = {0}, y = {1}", StructA1.x, StructA1.y);
Console.Write("StructA 2: ");
Console.WriteLine("x = {0}, y = {1}", StructA2.x, StructA2.y);
// Keep the console window open in debug mode.
Console.WriteLine("Press any key to exit.");
Console.ReadKey();
}
}
Structs Almost have same syntax as classes, But structs are more limited than classes:
• Within a struct declaration, fields cannot be initialized unless they are declared as const or static.
• A struct cannot declare a default constructor (a constructor without parameters) or a destructor.
• Structs are copied on assignment. When a struct is assigned to a new variable, all the data is copied, and any modification to the new copy does not change the data for the original copy.
• Structs are value types but classes are reference types.
• structs can be instantiated without using a new operator.
• Structs can declare constructors that have parameters.
• A struct cannot support the inheritance.
• All structs inherit directly from System.ValueType, which inherits from System.Object.
• A struct can implement interfaces.
• A struct can be used as a nullable type and can be assigned a null value.
