JavaScript和可见性
我是JavaScript新手,现在我遇到了一个问题:当我启动网页时,btn是不可见的,但我需要它在鼠标向下移动之前可见。以下是脚本:JavaScript和可见性,javascript,html,webpage,hidden,Javascript,Html,Webpage,Hidden,我是JavaScript新手,现在我遇到了一个问题:当我启动网页时,btn是不可见的,但我需要它在鼠标向下移动之前可见。以下是脚本: var start= false; var racket = document.getElementById("racket"); var btn = document.getElementById("btn"); btn.style.visibility = "visible"; btn.onmousedown = Start(); function Star
var start= false;
var racket = document.getElementById("racket");
var btn = document.getElementById("btn");
btn.style.visibility = "visible";
btn.onmousedown = Start();
function Start() {
btn.style.visibility = "hidden";
start = true;
document.onclick = RacketClick();
}
function RacketClick() {
}
当我启动网页时,btn被隐藏。。。你能帮我吗
UPD 1 HTML代码和CSS代码:
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
<meta charset="utf-8" />
<title>Main</title>
<link href="/css/default.css" rel="stylesheet" />
<script src="/js/mymain.js"></script>
</head>
<body>
<div id="racket"></div>
<div id="btn"></div>
</body>
</html>
#racket {
top: 100%;
margin-top: -200px;
left: 50%;
margin-left: -77px;
position: absolute;
background-image: url('/images/racket.png');
width: 154px;
height: 250px;
animation-name: racketanimation;
animation-iteration-count: infinite;
animation-delay: 0s;
animation-fill-mode: forwards;
animation-duration: 4s;
animation-timing-function: linear;
animation-direction:alternate;
}
@keyframes racketanimation {
from {
transform: rotateX(40deg);
}
to {
transform: rotateX(55deg);
}
}
#btn {
top: 50%;
left: 50%;
position: absolute;
margin-top: -128px;
margin-left: -128px;
height: 256px;
width: 256px;
background-image: url('/images/playnowborder.png');
animation-iteration-count: infinite;
animation-delay: 0s;
animation-fill-mode: forwards;
animation-duration: 10s;
animation-name: clicken;
animation-timing-function: linear;
}
@keyframes clicken {
from {
transform: rotate(360deg);
}
to {
transform: rotate(0deg);
}
}
我也是这个网站的新手!我想要你的答案,但我没有投票权……你应该使用没有括号的函数赋值:
btn.onmousedown = Start;
否则,函数开始会在赋值时执行,您的按钮会立即隐藏。您应该使用不带括号的函数赋值:
btn.onmousedown = Start;
否则,函数Start将在分配时执行,您的按钮将立即隐藏。这一行是您的问题:
btn.onmousedown = Start();
您正在执行函数start,并将未定义的结果分配给btn.onmousedown。你应该:
btn.onmousedown = Start;
如果没有括号,则分配函数,而不是调用函数。这一行是您的问题:
btn.onmousedown = Start();
您正在执行函数start,并将未定义的结果分配给btn.onmousedown。你应该:
btn.onmousedown = Start;
没有括号,分配函数,不调用函数。你用CSS隐藏了它吗?不,我没有,我用JavaScript有问题,不是用HTML和CSSdocument。onclick=RacketClick&&btn.onmousedown=start你用CSS隐藏了它吗?不,我没有,我对JavaScript有问题,而不是HTML和CSSdocument.onclick=RacketClick&&btn.onmousedown=Start