Type.GetFields() Method is used to get the fields of the current Type. There are 2 methods in the overload list of this method as follows:
- GetFields() Method
- GetFields(BindingFlags) Method
GetFields() Method
This method is used to return all the public fields of the current Type.
Syntax: public System.Reflection.FieldInfo[] GetFields ();
Return Value: This method returns an array of FieldInfo objects representing all the public fields defined for the current Type. Or, an empty array of type FieldInfo, if no public fields are defined for the current Type.
Below programs illustrate the use of Type.GetFields() Method:
Example 1:
// C# program to demonstrate the // Type.GetFields() Method using System;
using System.Globalization;
using System.Reflection;
class GFG {
// Main Method
public static void Main()
{
// Declaring and initializing object of Type
Type objType = typeof (Student);
// try-catch block for handling Exception
try {
// Getting array of Fields by
// using GetField() Method
FieldInfo[] info = objType.GetFields(BindingFlags.Public | BindingFlags.Static);
// Display the Result
Console.Write( "Fields of current type is as Follow: " );
for ( int i = 0; i < info.Length; i++)
Console.WriteLine( " {0}" , info[i]);
}
// catch ArgumentNullException here
catch (ArgumentNullException e)
{
Console.Write( "name is null." );
Console.Write( "Exception Thrown: " );
Console.Write( "{0}" , e.GetType(), e.Message);
}
}
} // Defining class Student public class Student
{ public string Name = "Rahul" ;
public string Dept = "Electrical" ;
public int Roll = 10;
public static int id = 02;
} |
Fields of current type is as Follow: System.Int32 id
Example 2: For if no public field is defined
// C# program to demonstrate the // Type.GetFields(String) Method using System;
using System.Globalization;
using System.Reflection;
class GFG {
// Main Method
public static void Main()
{
// Declaring and initializing object of Type
Type objType = typeof (Student);
// try-catch block for handling Exception
try {
// Getting array of Fields by
// using GetField() Method
FieldInfo[] info = objType.GetFields();
// Display the Result
Console.Write( "Public Fields of current type is as follow: " );
if (info.Length != 0)
{
for ( int i = 0; i < info.Length; i++)
Console.WriteLine( " {0}" , info[i]);
}
else
Console.WriteLine( "No public fields are defined for the current Type." );
}
// catch ArgumentNullException here
catch (ArgumentNullException e)
{
Console.Write( "name is null." );
Console.Write( "Exception Thrown: " );
Console.Write( "{0}" , e.GetType(), e.Message);
}
}
} // Defining class Student public class Student
{ } |
Public Fields of current type is as follow: No public fields are defined for the current Type.
GetFields(BindingFlags) Method
This method is used to search for the fields defined for the current Type, using the specified binding when overridden in a derived class, constraints.
Syntax: public abstract System.Reflection.FieldInfo[] GetFields (System.Reflection.BindingFlags bindingAttr);
Here, bindingAttr is a bitmask comprised of one or more BindingFlags that specify how the search is conducted or Zero, to return null.Return Value: This method returns an array of FieldInfo objects representing all fields defined for the current Type that match the specified binding constraints. Or, an empty array of type FieldInfo, if no fields are defined for the current Type, or if none of the defined fields match the binding constraints.
Below programs illustrate the use of the above-discussed method:
Example 1:
// C# program to demonstrate the // Type.GetField(String) // Method using System;
using System.Globalization;
using System.Reflection;
class GFG {
// Main Method
public static void Main()
{
// Declaring and initializing object of Type
Type objType = typeof (Student);
// Creating try-catch block for handling Exception
try {
// You must specify either BindingFlags.Instance or BindingFlags.Static
// and Specify BindingFlags.Public
// to include public fields in the search.
BindingFlags battr = BindingFlags.Public | BindingFlags.Instance;
// Getting FieldInfo by
// using GetField() Method
FieldInfo info = objType.GetField( "Name" , battr);
// Display the Result
Console.WriteLine( "FieldInfo is - {0}" ,info);
}
// catch ArgumentNullException here
catch (ArgumentNullException e)
{
Console.Write( "name is null." );
Console.Write( "Exception Thrown: " );
Console.Write( "{0}" , e.GetType(), e.Message);
}
}
} // Defining class Student public class Student
{ public string Name = "Rahul" ;
public string Dept = "Electrical" ;
public int Roll = 10;
} |
FieldInfo is - System.String Name
Example 2: For ArgumentNullException
// C# program to demonstrate the // Type.GetFields(String) // Method using System;
using System.Globalization;
using System.Reflection;
class GFG {
// Main Method
public static void Main()
{
// Declaring and initializing object of Type
Type objType = typeof (Book);
// Creating try-catch block for handling Exception
try {
// Getting array of Fields by
// using GetField() Method
FieldInfo[] info = objType.GetFields(BindingFlags.NonPublic | BindingFlags.Instance);
// Display the Result
Console.WriteLine( "Fields of current type is as follow :-" );
for ( int i=0; i<info.Length; i++)
Console.WriteLine( " {0}" ,info[i]);
}
// catch ArgumentNullException here
catch (ArgumentNullException e)
{
Console.Write( "name is null." );
Console.Write( "Exception Thrown: " );
Console.Write( "{0}" , e.GetType(), e.Message);
}
}
} // Defining class Student public class Book
{ public string Name = "Element of Physics" ;
public string Author = "R.S. Agrwal" ;
public static int Price = 500;
private string metadata = "djdieeiie" ;
} |
FieldInfo is - System.String Name
Reference: