Camera.allCameras

Description

Returns all enabled cameras in the scene.

var count : int = Camera.allCameras.Length;
print ("We've got " + count + " cameras");

using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour {
    public int count = Camera.allCameras.Length;
    void Example() {
        print("We've got " + count + " cameras");
    }
}