11.1.1 Default constructors
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11.1.1 Default constructors
All value types implicitly declare a public parameterless instance
constructor called the default constructor.
The default constructor returns a zero-initialized instance known as the
default value for the value type:
?For all simple-types, the default value is the value produced by a bit
pattern of all zeros:
For sbyte, byte, short, ushort, int, uint, long, and ulong, the default
value is 0.
For char, the default value is 抃x0000?
For float, the default value is 0.0f.
For double, the default value is 0.0d.
For decimal, the default value is 0.0m.
For bool, the default value is false.
?For an enum-type E, the default value is 0.
?For a struct-type, the default value is the value produced by setting all
value type fields to their default
value and all reference type fields to null.
Like any other instance constructor, the default constructor of a value
type is invoked using the new
operator. [Note: For efficiency reasons, this requirement is not intended
to actually have the implementation
generate a constructor call. end note] [Example: In the example below,
variables i and j are both initialized
to zero.
class A
{
void F() {
int i = 0;
int j = new int();
}
}
end example]
Because every value type implicitly has a public parameterless instance
constructor, it is not possible for a
struct type to contain an explicit declaration of a parameterless
constructor. A struct type is however
permitted to declare parameterized instance constructors (?8.3.8).
All value types implicitly declare a public parameterless instance
constructor called the default constructor.
The default constructor returns a zero-initialized instance known as the
default value for the value type:
?For all simple-types, the default value is the value produced by a bit
pattern of all zeros:
For sbyte, byte, short, ushort, int, uint, long, and ulong, the default
value is 0.
For char, the default value is 抃x0000?
For float, the default value is 0.0f.
For double, the default value is 0.0d.
For decimal, the default value is 0.0m.
For bool, the default value is false.
?For an enum-type E, the default value is 0.
?For a struct-type, the default value is the value produced by setting all
value type fields to their default
value and all reference type fields to null.
Like any other instance constructor, the default constructor of a value
type is invoked using the new
operator. [Note: For efficiency reasons, this requirement is not intended
to actually have the implementation
generate a constructor call. end note] [Example: In the example below,
variables i and j are both initialized
to zero.
class A
{
void F() {
int i = 0;
int j = new int();
}
}
end example]
Because every value type implicitly has a public parameterless instance
constructor, it is not possible for a
struct type to contain an explicit declaration of a parameterless
constructor. A struct type is however
permitted to declare parameterized instance constructors (?8.3.8).
- 11.1.1 Default constructors
- 17.10.4 Default constructors
- Day14-46.Default constructors
- Avoid non-default constructors in fragments
- Constructors
- Constructors
- Fragment:关于Avoid non-default constructors in fragments的错误
- Fragment:关于Avoid non-default constructors in fragments的错误
- Avoid non-default constructors in fragments的解决方法
- Fragment:关于Avoid non-default constructors in fragments的错误
- 关于Avoid non-default constructors in fragments的错误
- Fragment:关于Avoid non-default constructors in fragments的错误
- Fragment:关于Avoid non-default constructors in fragments的错误
- Avoid non-default constructors in fragments:use a default constructor plus Fragment#SetArguments(Bu)
- Android Fragment avoid non-default constructors in fragments use a default constructor plus fragment
- Avoid non-default constructors in fragments: use a default constructor plus Fragment报错的解决方法
- Avoid non-default constructors in fragments: use a default constructor plus setArguments()错误提示解决方法
- Error:Error: Avoid non-default constructors in fragments: use a default construct
- 10.8.1 Fully qualified names
- 10.9 Automatic memory management
- 10.10 Execution order
- 11. Types
- 11.1 Value types
- 11.1.1 Default constructors
- 11.1.2 Struct types
- 11.1.3 Simple types
- 11.1.4 Integral types
- 11.1.5 Floating point types
- 11.1.6 The decimal type
- 11.1.7 The bool type
- 11.1.8 Enumeration types
- 11.2 Reference types