How to Generate Random Numbers and range of numbers in Dart or Flutter Programming with example
This tutorial shows multiple ways to Generate Random Numbers in the Dart programming language.
A random number is a unique number generated between a minimum and maximum value for multiple requests
The returned number is always between the ranges of values provided.
Dart random Number Generator example
Dart provides dart:math
that contains a Random
class to provide a random generator.
It provides the nextInt
method takes a maximum value and returns a random number.
int nextInt(int max)
minimum number is taken as zero as a minimum and the maximum number is the given max value.
Here is a simple example to generate Random Generator
import 'dart: math';
main() {
var random = Random();
print(random.nextInt(10)); //Random number between 0 to 10
print(random.nextInt(100)); //Random number between 0 to 100
print(random.nextInt(200)); //Random number between 0 to 100
print(random.nextInt(1000)); //Random number between 0 to 1000
}
- Imported the
dart:math
package into a program using theimport
keyword - Create a Random variable using the
var
keyword - Call nextInt() with seed number.
- Random Number always generated between 0 to seed number
Output:
4
70
47
294
Dart random Number Generator within a range example
This is a generating random number between min and max value of ranges example
.
import 'dart:math';
main() {
var random = Random();
int min = 10;
int max = 20;
var randomNumber = min + random.nextInt(max - min);
print("$randomNumber is random number between $min and $max");
print(randomNumber);
}
Output:
19 is a random number between 10 and 20
19
How to generate a random number in dart excluding a particular number?
For example, You want to generate a random number between 0 to 10 and the generated random number must not be 5.
Here is an example program to generate a Random Number excluding given number
import 'dart:math';
main() {
var random = Random();
var excludeNumber = 5;
var randomNumber;
do {
randomNumber = random.nextInt(10);
} while (randomNumber == excludeNumber);
print(randomNumber);
}