Question

请考虑以下情况，其中我É定义了字符串\U00000045\U00000301。

1）https://www.fileformat.info/info/unicode/char/0045/index.htm
2）https://www.fileformat.info/info/unicode/char/0301/index.htm

受varchar(1)限制的表是否会将其视为有效的1个字符输入。或者它会被拒绝，因为它被认为是一个2字符输入？

SQL如何通常使用字素来处理字符串的长度？

Answer 1

我对这个查询看起来很傻，但仍然：

func makeShoot() {
    let Shoot:ShootClass = ShootClass.init()
    Shoot.physicsBody = SKPhysicsBody(texture: Shoot.texture!,
                                     size: Shoot.texture!.size())
    Shoot.position = (self.Shoot?.position)!
    Shoot.currentPosition = (self.Shoot?.position)!
    Shoot.physicsBody?.isDynamic = true
    Shoot.physicsBody?.allowsRotation = false
    Shoot.physicsBody?.affectedByGravity = false
    Shoot.physicsBody?.friction = 0
    Shoot.physicsBody?.restitution = 1
    Shoot.physicsBody?.mass = 1
    Shoot.physicsBody?.linearDamping = 0.0
    Shoot.physicsBody?.angularDamping = 0.0
    Shoot.physicsBody?.categoryBitMask = ShootCategory
    Shoot.physicsBody?.collisionBitMask = BorderCategory
    Shoot.physicsBody?.contactTestBitMask = BorderCategory

    PlayingView.addChild(Shoot);

    Shoot.physicsBody?.applyImpulse(CGVector(dx: 100, dy: 100))

    self.moveNodeToLocation(Shoot: Shoot)
}



override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
    let curTouch = touches.first!
    let curPoint = curTouch.location(in: self)
    if ((curPoint.x > 103.5 && curPoint.y > 50.0) || (curPoint.x < 840.0 && curPoint.y > 50.0)) {
        StartingPoint = touches.first?.location(in: self)
        direction?.isHidden = false
        direction?.setScale(0.50)
        FirstTouchLocater = SKSpriteNode(imageNamed: "ic_Shootz");
        FirstTouchLocater.position = curPoint
        FirstTouchLocater.alpha = 0.5
        self.addChild(FirstTouchLocater);

    }
    else{
        self.direction?.isHidden = true
    }
}

override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {

    let point:CGPoint = (touches.first?.location(in: self))!

    if point.y < 40 {
        return
    }

    if !(isTouch!) {
        isTouch = true
    }


    let dy:CGFloat = StartingPoint!.y - point.y

    let size:CGFloat = dy*10/self.frame.height

    if size < 2 && size > 0.50 {
        direction?.setScale(size)
    }
     print("size ======> \(size)")




    let curTouch = touches.first!
    let curPoint = curTouch.location(in: self)

    if (curPoint.x <= ((StartingPoint?.x)! + 20.0)) &&  ((curPoint.x + 20.0) >= (StartingPoint?.x)!) && (curPoint.y <= ((StartingPoint?.y)! + 20.0)) &&  ((curPoint.y + 20.0) >= (StartingPoint?.y)!){
        self.direction?.isHidden = true
        FirstTouchLocater?.isHidden = true
    }
    else if ((curPoint.x > 103.5 && curPoint.y > 50.0) || (curPoint.x < 840.0 && curPoint.y > 50.0)) {
        let deltaX = (self.direction?.position.x)! - curPoint.x
        let deltaY = (self.direction?.position.y)! - curPoint.y
        let angle = atan2(deltaY, deltaX)

        let DegreesToRadians = CGFloat.pi / 180

        self.direction?.zRotation = angle + 90 * DegreesToRadians
        self.direction?.isHidden = false
        FirstTouchLocater?.isHidden = false
    }
    else{
        self.direction?.isHidden = true
        FirstTouchLocater?.isHidden = true
    }
}

override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
    if direction?.isHidden == false {
        FirstTouchLocater.removeFromParent()
        direction?.isHidden = true
        direction?.setScale(0.1)
        if timeThrow == nil && isTouch!
        {
            isTouch = false
            counterY = 0;

            let touch = touches.first
            let touchLocation = touch?.location(in: self)
            lastTouch = touchLocation
            lastTouch1 = touchLocation

            ShootThrow = 2

            timeThrow = Timer.scheduledTimer(timeInterval: 0.1, target: self, selector: #selector(self.loadScreen), userInfo: nil, repeats: true)
        }
    }
}

func moveNodeToLocation(Shoot:SKSpriteNode) {
    let dx = (lastTouch?.x)! - Shoot.position.x
    let dy = (lastTouch?.y)! - Shoot.position.y

    let speed1:CGFloat = 424
    let hypo = hypot(dx, dy)

    let newX = (speed1 * dx) / hypo
    let newY = (speed1 * dy) / hypo
    Shoot.physicsBody?.velocity = CGVector(dx:newX, dy: newY)

}

修改

t=# with c(u) as (values( e'\U00000045\U00000301')) select u, u::varchar(1), u::varchar(2),char_length(u), octet_length(u) from c; u | u | u | char_length | octet_length ---+---+---+-------------+-------------- É | E | É | 2 | 3 (1 row)

SQL长度函数如何处理unicode字形？

1 个答案: