Type.GetField() Method is used to get a specific field of the current Type. There are 2 methods in the overload list of this method as follows:
- GetField(String) Method
- GetField(String, BindingFlags) Method
GetField(String) Method
This method is used to search for the public field with the specified name.
Syntax: public System.Reflection.FieldInfo GetField (string name);
Here, it takes the string containing the name of the data field to get.Return Value: This method returns an object representing the public field with the specified name if found otherwise, null.
Exception: This method throws ArgumentNullException if the name is null .
Below programs illustrate the use of Type.GetField() 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); // try-catch block for handling Exception try { // Getting FieldInfo by // using GetField(String) Method FieldInfo info = objType.GetField("Name"); // 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.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); // try-catch block for handling Exception try { // Getting FieldInfo by // using GetField() Method FieldInfo info = objType.GetField(null); // Display the Result Console.WriteLine("FieldInfo is: {0}", info); } // catch ArgumentNullException here catch (ArgumentNullException e) { Console.WriteLine("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; } |
name is null. Exception Thrown: System.ArgumentNullException
GetField(String, BindingFlags) Method
This method is used to search for the specified field, using the specified binding constraints.
Syntax: public abstract System.Reflection.FieldInfo GetField (string name, System.Reflection.BindingFlags bindingAttr);
Parameters:
name: The string containing the name of the data field to get.
bindingAttr: It 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 object representing the field that matches the specified requirements if found otherwise, null.
Exception: This method throws ArgumentNullException if name is null.
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); // 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.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); // 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(null, battr); // Display the Result Console.WriteLine("FieldInfo is: {0}", info); } // catch ArgumentNullException here catch (ArgumentNullException e) { Console.WriteLine("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; } |
Output:
name is null. Exception Thrown: System.ArgumentNullException
Reference:
