C# | Params
Params is an important keyword in C#. It is used as a parameter which can take the variable number of arguments.
Important Point About Params Keyword :
- It is useful when programmer don’t have any prior knowledge about the number of parameters to be used.
- Only one Params keyword is allowed and no additional Params will be allowed in function declaration after a params keyword.
- The length of params will be zero if no arguments will be passed.
Examples: To illustrate the use of params keyword
- Simple program to show the params keyword usage
// C# program to illustrate the
// use of params keyword
using
System;
namespace
Examples {
class
Beginner {
// function containing params parameters
public
static
int
Add(
params
int
[] ListNumbers)
{
int
total = 0;
// foreach loop
foreach
(
int
i
in
ListNumbers)
{
total += i;
}
return
total;
}
// Driver Code
static
void
Main(
string
[] args)
{
// Calling function by passing 5
// arguments as follows
int
y = Add(12,13,10,15,56);
// Displaying result
Console.WriteLine(y);
}
}
}
Output :
106
Explanation : There is no need to define the size of the array because using params keyword in above program, the Integer data will be in the form:
ListNumbers
[0] 12
[1] 13
[2] 10
[3] 15
[4] 56 - Object type Params will allow any type of arguments and any number of arguments as follows :
// C# program to illustrate the
// use of object type params
using
System;
namespace
Example2 {
class
Beginner {
// function using object type params
public
void
result(
params
object
[] array)
{
for
(
int
i = 0; i < array.Length; i++)
{
// Display result
Console.WriteLine(array[i]);
}
}
// Driver Code
static
void
Main(
string
[] args)
{
Beginner gfg =
new
Beginner();
// Variable length arguments
gfg.result(
"Beginner"
,
"GFG"
,
"ProGeek Cup 2.0"
,
"G4G"
,
"100"
);
}
}
}
Output :
Beginner GFG ProGeek Cup 2.0 G4G 100
Explanation : In above program the object type params parameter can accept any type of data and any number of arguments.