Input.GetMouseButtonDown 获取鼠标按钮按下

# [Input](Input.html).GetMouseButtonDown 获取鼠标按钮按下

static function *GetMouseButtonDown* (*button* : int) : bool

*Description* 描述

Returns true during the frame the user pressed the given mouse button.

在用户按下指定鼠标按键的那一帧返回 true。

You need to call this function from the [Update](../MonoBehaviour/MonoBehaviour.Update.html) function, since the
state gets reset each frame. It will not return true until the user has released
the mouse button and pressed it again. button values are 0 for left button, 1
for right button, 2 for the middle button.

你需要在 Update 方法中调用这个方法，此后每一帧重置状态时，它将不会返回 true 除非用户释放这个鼠标按钮然后重新按下它。按钮值设定为 0 对应左键 ，
1 对应右键 ， 2 对应中键。

* [C#](#)
* [JavaScript](#)

```
using UnityEngine;
using System.Collections;

public class example : MonoBehaviour {
	void Update() {
		if (Input.GetMouseButtonDown(0))
			Debug.Log("Pressed left click.");

if (Input.GetMouseButtonDown(1))
			Debug.Log("Pressed right click.");

if (Input.GetMouseButtonDown(2))
			Debug.Log("Pressed middle click.");

}
}
```

```
// Detects clicks from the mouse and prints a message
// depending on the click detected.
//检测到鼠标点击就输出信息
//取决于点击的键值

function Update() {
	if(Input.GetMouseButtonDown(0))
		Debug.Log("Pressed left click.");
	if(Input.GetMouseButtonDown(1))
		Debug.Log("Pressed right click.");
	if(Input.GetMouseButtonDown(2))
		Debug.Log("Pressed middle click.");
}
```