Actionscript 3 AS3：仅按单键

我正在尝试创建一个平台游戏，我有跑，跳和双跳工作。现在我的问题是，我希望玩家按下跳跃按钮，英雄只跳跃一次，而不是连续跳跃。如果我按住“向上”按钮，它将继续跳跃，这是我不想要的，我只想让它执行一次跳跃，即使按键仍被按住。我想要同样的双人跳远，我怎样才能做到这一点

package 
{
    import flash.display.MovieClip;
    import flash.events.Event;
    import flash.events.KeyboardEvent;
    import flash.ui.Keyboard;

    public class Player extends MovieClip
    {
        //Player run speed setting
        var RunSpeed:Number = 8;
        //Player key presses
        var RightKeyPress:Boolean = false;
        var LeftKeyPress:Boolean = false;
        var UpKeyPress:Boolean = false;
        //Jump variables
        var Gravity:Number = 1.5;
        var JumpPower:Number = 0;
        var CanJump:Boolean = false;
        var DoubleJump:Boolean = false;

        public function Player()
        {
            // constructor code
            stage.addEventListener(KeyboardEvent.KEY_DOWN,KeyPressed);
            addEventListener(Event.ENTER_FRAME,Update);
            stage.addEventListener(KeyboardEvent.KEY_UP,KeyReleased);
        }

        function KeyPressed(event:KeyboardEvent)
        {
            //When Key is Down
            if (event.keyCode == 39)
            {
                RightKeyPress = true;
            }

            if (event.keyCode == 37)
            {
                LeftKeyPress = true;
            }

            if (event.keyCode == 38)
            {
                UpKeyPress = true

            }
        }

        function Update(event:Event)
        {
            //Adding gravity to the game world
            JumpPower +=  Gravity;
            //if player is more than 300 on the y-axis
            if (this.y > 300)
            {
                //Player stays on the ground and can jump
                JumpPower = 0;
                CanJump = true;
                DoubleJump = false;
            }

            //If player is on floor and right key is pressed then run right
            if ((RightKeyPress && CanJump))
            {
                x +=  RunSpeed;
                gotoAndStop('Run');
                scaleX = 1;
            }
            else if ((LeftKeyPress && CanJump))
            {
                //Otherwise if on floor and left key is pressed run left
                x -=  RunSpeed;
                gotoAndStop('Run');
                scaleX = -1;
            }
            else if ((UpKeyPress && CanJump))
            {
                //Otherwise if on floor and up key is pressed then jump
                JumpPower = -15;
                CanJump = false;
                gotoAndStop('Jump');
                DoubleJump = true;
            }

            //If on floor and right and up key are pressed then jump
            if ((RightKeyPress && UpKeyPress && CanJump))
            {
                JumpPower = -15;
                CanJump = false;
                gotoAndStop('Jump');
                DoubleJump = true;
            }

            //If on floor and left and up key are pressed then jump
            if ((LeftKeyPress && UpKeyPress && CanJump))
            {
                JumpPower = -15;
                CanJump = false;
                gotoAndStop('Jump');
                DoubleJump = true;
            }

            //If jumped and right key is pressed then move right
            if ((RightKeyPress && CanJump == false))
            {
                x +=  RunSpeed;
                scaleX = 1;
            }
            else if ((LeftKeyPress && CanJump == false))
            {
                //Otherwise if jumped and left key is pressed then move left
                x -=  RunSpeed;
                scaleX = -1;
            }

            //If in air and able to doublejump and pressed up key, then double jump
            if (UpKeyPress && DoubleJump && JumpPower > -2)
            {
                JumpPower = -13;
                DoubleJump = false;
                gotoAndStop('DoubleJump');
            }

            //If on floor and no key is presses stay idle
            if ((!RightKeyPress && !LeftKeyPress && CanJump))
            {
                gotoAndStop('Idle');
            }

            this.y +=  JumpPower;
        }

        function KeyReleased(event:KeyboardEvent)
        {
            if (event.keyCode == 39)
            {
                event.keyCode = 0;
                RightKeyPress = false;
            }

            if (event.keyCode == 37)
            {
                event.keyCode = 0;
                LeftKeyPress = false;
            }

            if (event.keyCode == 38)
            {
                event.keyCode = 0;
                UpKeyPress = false;
            }
        }
    }
}

---

我怀疑发生的情况是，一旦你的玩家的y值满足条件

如果（this.y>300）

你允许他再次跳跃，那么只要按住键，他就会跳跃，因为

UpKeyPress&&CanJump

都是真的

我的猜测是这样做可能会让你更接近你的答案

在更新功能中：

function Update(event:Event)
{
    //Adding gravity to the game world
    JumpPower +=  Gravity;
    //if player is more than 300 on the y-axis
    if (this.y > 300)
    {
        //Player stays on the ground and can jump
        JumpPower = 0;
        // Do not allow another jump until the UpKey is pressed
        //CanJump = true;
        //DoubleJump = false;
    }
    ...

function KeyPressed(event:KeyboardEvent)
{
    //When Key is Down
    if (event.keyCode == 39)
    {
        RightKeyPress = true;
    }

    if (event.keyCode == 37)
    {
        LeftKeyPress = true;
    }

    if (event.keyCode == 38)
    {
        UpKeyPress = true
        // Do not allow another jump until the UpKey is pressed
        if (this.y > 300)
        {
            CanJump = true;
            DoubleJump = false;
        }
    }
}

然后在按键功能中：

function Update(event:Event)
{
    //Adding gravity to the game world
    JumpPower +=  Gravity;
    //if player is more than 300 on the y-axis
    if (this.y > 300)
    {
        //Player stays on the ground and can jump
        JumpPower = 0;
        // Do not allow another jump until the UpKey is pressed
        //CanJump = true;
        //DoubleJump = false;
    }
    ...

function KeyPressed(event:KeyboardEvent)
{
    //When Key is Down
    if (event.keyCode == 39)
    {
        RightKeyPress = true;
    }

    if (event.keyCode == 37)
    {
        LeftKeyPress = true;
    }

    if (event.keyCode == 38)
    {
        UpKeyPress = true
        // Do not allow another jump until the UpKey is pressed
        if (this.y > 300)
        {
            CanJump = true;
            DoubleJump = false;
        }
    }
}

---

我还支持shaunhusain的建议，即设置断点并熟悉调试代码。

您是否尝试过在双跳转发生的位置设置断点？在我看来，布尔逻辑应该是正确的，但你一定是因为某种原因反复出现在那个块？尝试在更新函数中的关键点追踪布尔值。@shaunhusain:Break point？我对AS3有点陌生，所以我知道的还不多，但我学得很快。没问题，检查一下这个链接，或者用谷歌搜索一下，这篇文章的后半部分可能会有帮助，但它很长。为了将来的参考，有一个键盘类列举了一些键，所以你可以用Keyboard.UP替换38。