我想这个this.bgImage指代不明确
时间: 2023-05-24 07:01:07 浏览: 42
对于这个问题,我可以给您一些解释。this.bgImage通常用于设定页面的背景图片,但具体指代则取决于该变量在代码中的定义和使用。通常情况下,开发者应该在代码中明确指出变量的作用和使用场景,以免引起混淆。如果您需要更为详细的解答,我可以为您提供更多资料和资源。
相关问题
const ViewRender = memo((props: ViewProps) => { const { pointData, pageData, width, dragStop, onDragStart, onResizeStop, preview } = props; const FixedData: Array<PointDataItem> = pointData.filter(e => e.item.type == 'Fixed') const nFixedData: Array<PointDataItem> = pointData.filter(e => e.item.type != 'Fixed') return ( (!preview ? ( <GridLayout cols={24} rowHeight={2} margin={[0, 0]} width={width} // @ts-expect-error onDragStop={debounce(dragStop, 500)} onDragStart={onDragStart} onResizeStop={onResizeStop} style={{ minHeight: '100vh', backgroundSize: '100%', backgroundRepeat: 'no-repeat', backgroundColor: pageData && pageData.bgColor, backgroundImage: pageData && pageData.bgImage ? `url(${pageData.bgImage[0].url})` : 'initial' }} > {pointData.map((value: PointDataItem) => ( <div key={value.id} data-grid={value.point} className={onDragStart && styles.dragItem} style={{ overflow: value.item.type == 'Fixed' ? 'visible' : 'hidden' }}> {value.item.type == 'Fixed' ? ( <div style={{ transform: `translateY(-${value.item.config.y}px)` }}> <DynamicEngine {...(value.item as any)} isTpl={false} /> </div> ) : ( <DynamicEngine {...(value.item as any)} isTpl={false} /> )} </div> ))} </GridLayout> ) : ( <> <GridLayout cols={24} rowHeight={2} margin={[0, 0]} width={width} style={{ minHeight: '100vh', backgroundSize: '100%', backgroundRepeat: 'no-repeat', backgroundColor: pageData && pageData.bgColor, backgroundImage: pageData && pageData.bgImage ? `url(${pageData.bgImage[0].url})` : 'initial' }}> {nFixedData.map((value: PointDataItem) => ( <div key={value.id} data-grid={value.point}> <DynamicEngine {...(value.item as any)} isTpl={false} /> </div> ))} </GridLayout> {FixedData.map((value: PointDataItem) => ( <div key={value.id} data-grid={value.point}> <DynamicEngine {...(value.item as any)} isTpl={false} /> </div> ))} </> )) ) })帮我优化这段代码
这段代码可以进行一些小的优化,如下:
1. 可以将`const { pointData, pageData, width, dragStop, onDragStart, onResizeStop, preview } = props;`解构放在函数参数中,这样可以避免在函数体中使用`props.`的方式来获取参数。
2. 可以将`pointData.map((value: PointDataItem) => (`中的`value`改为`item`,以更好地表达其含义。
3. 可以将`value.item`改为`item`,在整个代码中保持一致。
4. 可以将`value.item.type`改为`itemType`,以更好地表达其含义。
5. 可以使用可选链运算符`?.`来避免出现`pageData`或`pageData.bgImage`为空时的报错。
6. 可以将`onDragStop={debounce(dragStop, 500)}`中的`500`提取成一个常量或变量。
7. 可以将`<DynamicEngine {...(value.item as any)} isTpl={false} />`提取出来成为一个变量,以避免重复代码。
综上所述,代码可以改写为:
```
const ViewRender = memo(({ pointData, pageData, width, dragStop, onDragStart, onResizeStop, preview }: ViewProps) => {
const { bgColor = '', bgImage = [] } = pageData || {};
const FixedData: Array<PointDataItem> = pointData.filter(e => e.itemType === 'Fixed');
const nFixedData: Array<PointDataItem> = pointData.filter(e => e.itemType !== 'Fixed');
const dynamicEngine = (item: any) => (
<DynamicEngine {...(item as any)} isTpl={false} />
);
return (
(!preview ? (
<GridLayout
cols={24}
rowHeight={2}
margin={[0, 0]}
width={width}
onDragStop={debounce(dragStop, 500)}
onDragStart={onDragStart}
onResizeStop={onResizeStop}
style={{
minHeight: '100vh',
backgroundSize: '100%',
backgroundRepeat: 'no-repeat',
backgroundColor: bgColor,
backgroundImage: bgImage[0]?.url || 'initial',
}}
>
{pointData.map(({ id, point, itemType, item }) => (
<div key={id} data-grid={point} className={onDragStart && styles.dragItem} style={{
overflow: itemType === 'Fixed' ? 'visible' : 'hidden',
}}>
{itemType === 'Fixed' ? (
<div style={{ transform: `translateY(-${item?.config?.y}px)` }}>
{dynamicEngine(item)}
</div>
) : (
dynamicEngine(item)
)}
</div>
))}
</GridLayout>
) : (
<>
<GridLayout
cols={24}
rowHeight={2}
margin={[0, 0]}
width={width}
style={{
minHeight: '100vh',
backgroundSize: '100%',
backgroundRepeat: 'no-repeat',
backgroundColor: bgColor,
backgroundImage: bgImage[0]?.url || 'initial',
}}>
{nFixedData.map(({ id, point, item }) => (
<div key={id} data-grid={point}>
{dynamicEngine(item)}
</div>
))}
</GridLayout>
{FixedData.map(({ id, point, item }) => (
<div key={id} data-grid={point}>
{dynamicEngine(item)}
</div>
))}
</>
))
);
});
```
帮我用js写一个飞机大战
好的,我会尽力帮您实现这个功能。
以下是一个简单的飞机大战的JavaScript代码示例:
```
// 创建画布
var canvas = document.createElement('canvas');
var ctx = canvas.getContext('2d');
canvas.width = 512;
canvas.height = 480;
document.body.appendChild(canvas);
// 背景图片
var bgReady = false;
var bgImage = new Image();
bgImage.onload = function () {
bgReady = true;
};
bgImage.src = "background.png";
// 飞机图片
var planeReady = false;
var planeImage = new Image();
planeImage.onload = function () {
planeReady = true;
};
planeImage.src = "plane.png";
// 游戏对象
var plane = {
speed: 256, // 移动速度
x: 0,
y: 0
};
var enemy = {
x: 0,
y: 0
};
var enemiesCaught = 0;
// 处理键盘控制
var keysDown = {};
addEventListener("keydown", function (e) {
keysDown[e.keyCode] = true;
}, false);
addEventListener("keyup", function (e) {
delete keysDown[e.keyCode];
}, false);
// 更新游戏状态
var update = function (modifier) {
if (38 in keysDown) { // 上方向键
plane.y -= plane.speed * modifier;
}
if (40 in keysDown) { // 下方向键
plane.y += plane.speed * modifier;
}
if (37 in keysDown) { // 左方向键
plane.x -= plane.speed * modifier;
}
if (39 in keysDown) { // 右方向键
plane.x += plane.speed * modifier;
}
// 捕获敌机
if (
plane.x <= (enemy.x + 32)
&& enemy.x <= (plane.x + 32)
&& plane.y <= (enemy.y + 32)
&& enemy.y <= (plane.y + 32)
) {
++enemiesCaught;
reset();
}
};
// 重新开始游戏
var reset = function () {
plane.x = canvas.width / 2;
plane.y = canvas.height / 2;
// 随机生成敌机位置
enemy.x = 32 + (Math.random() * (canvas.width - 64));
enemy.y = 32 + (Math.random() * (canvas.height - 64));
};
// 渲染游戏画面
var render = function () {
if (bgReady) {
ctx.drawImage(bgImage, 0, 0);
}
if (planeReady) {
ctx.drawImage(planeImage, plane.x, plane.y);
}
ctx.fillStyle = "rgb(250, 250, 250)";
ctx.font = "24px Helvetica";
ctx.textAlign = "left";
ctx.textBaseline = "top";
ctx.fillText("敌机已捕获: " + enemiesCaught, 32, 32);
};
// 控制游戏主循环
var main = function () {
var now = Date.now();
var delta = now - then;
update(delta / 1000);
render();
then = now;
requestAnimationFrame(main);
};
// 浏览器兼容性处理
var w = window;
requestAnimationFrame = w.requestAnimationFrame || w.webkitRequestAnimationFrame || w.msRequestAnimationFrame || w.mozRequestAnimationFrame;
// 启动游戏
var then = Date.now();
reset();
main();
```
您可以根据自己的需求修改这个代码,添加更多的游戏元素和特效。希望对您有所帮助!