凉鞋的 Unity 笔记 201. 第三轮循环：引入变量

201. 第三轮循环：引入变量

在这一篇，我们进行第三轮编辑-测试循环。

在之前我们编写了输出 Hello Unity 的脚本，如下:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;public class FirstGameObject : MonoBehaviour
{// Start is called before the first frame updatevoid Start(){print("Hello Unity"); // +}// Update is called once per framevoid Update(){}
}

如果我们要输出 10 次 Hello Unity 该怎么办呢？

答案很简单，就是复制十行 print(“Hello Unity”)，代码如下:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;public class FirstGameObject : MonoBehaviour
{// Start is called before the first frame updatevoid Start(){print("Hello Unity"); print("Hello Unity"); print("Hello Unity"); print("Hello Unity"); print("Hello Unity"); print("Hello Unity"); print("Hello Unity"); print("Hello Unity"); print("Hello Unity"); print("Hello Unity"); }// Update is called once per framevoid Update(){}
}

这样当我们运行场景后，结果如下:

总共输出了十次 Hello Unity。

此时我突然想要把输出十次 Hello Unity 改成输出十次 Hello C#。

那么最简单的方式，就是直接修改代码，如下：

using System.Collections;
using System.Collections.Generic;
using UnityEngine;public class FirstGameObject : MonoBehaviour
{// Start is called before the first frame updatevoid Start(){print("Hello C#"); print("Hello C#"); print("Hello C#"); print("Hello C#"); print("Hello C#"); print("Hello C#"); print("Hello C#"); print("Hello C#"); print("Hello C#"); print("Hello C#"); }// Update is called once per framevoid Update(){}
}

运行之后，结果如下：

但是这样太不优雅了，我们需要复制粘贴十次，如果我们有 100 个甚至 1000 个 Hello Unity，那么我们可能需要复制粘贴很多次，或者使用代码编辑器所提供的查找/替换功能完成。

比较优雅的方式就是引入一个变量，代码如下所示:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;public class FirstGameObject : MonoBehaviour
{// Start is called before the first frame updatevoid Start(){var textToPrint = "Hello C#";print(textToPrint); print(textToPrint); print(textToPrint); print(textToPrint); print(textToPrint);print(textToPrint); print(textToPrint); print(textToPrint); print(textToPrint); print(textToPrint); }// Update is called once per framevoid Update(){}
}

这样当我们想要输出十次 Hello World 那么我们只需要修改变量的值即可，如下所示：

using System.Collections;
using System.Collections.Generic;
using UnityEngine;public class FirstGameObject : MonoBehaviour
{// Start is called before the first frame updatevoid Start(){var textToPrint = "Hello World";print(textToPrint); print(textToPrint); print(textToPrint); print(textToPrint); print(textToPrint);print(textToPrint); print(textToPrint); print(textToPrint); print(textToPrint); print(textToPrint); }// Update is called once per framevoid Update(){}
}