Unity基础 随机数的使用

using UnityEngine;
using System.Collections;

public class NPCTest : MonoBehaviour {

    //NPC动作几率
    float[] probArray = {0.5f , 0.25f , 0.2f , 0.05f};  
    int probValue;    //NPC选择值

    // Use this for initialization
    void Start () {
    }
    
    // Update is called once per frame
    void Update () {
    }

    //选择函数，返回NPC的选项下标值
    int Choose(float[] probe)
    {
        float total = 0.0f;
        for (int i=0; i < probe.Length; i++) {
            total += probe[i];        
        }

        // Random.value方法返回一个0—1的随机数
        float randomPoint = Random.value * total;

        for (int i=0; i < probe.Length; i++) {
            if(randomPoint<probe[i])
                return i;
            else
                randomPoint -= probe[i];
        }

        return probe.Length - 1;
    }

    void OnGUI(){
        if( GUI.Button(new Rect(10,70,50,30),"Click") )
        {
            probValue = Choose(probArray);

            switch(probValue){
            case 0:
                Debug.Log ("NPC向我致敬！");
                break;
            case 1:
                Debug.Log ("NPC离开了！");
                break;
            case 2:
                Debug.Log ("NPC攻击我了！");
                break;
            case 3:
                Debug.Log ("NPC给我钱了！");
                break;
            default:
                Debug.Log("我没有碰到NPC");
                break;
            }
        }
    }
}