使用JS if语句通过按钮更改div类（我在做什么错）？

Question

 function navtoggle(elementRef) { if (document.getElementById('nav').className = 'closed') { document.getElementById('nav').className = 'open' } else if (document.getElementById('nav').className = 'open') { document.getElementById('nav').className = 'closed' }; }

 .closed { display: none; } .open { display: block; } #navget { width: 100px; height: 100px; box-shadow: 0px 0px 15px black; }

 <html> <head> <link rel="stylesheet" type="text/css" href="style.css"> <title>HTML Library</title> </head> <body> <div id="nav" class="closed"> <ul> <li><a href="index.html"><h1>HOME</h1></a> </li> </ul> </div> <button onclick="JavaScript: navtoggle(this);" id="navget">NAV</button> </body> </html>

Here is the Html: 这是HTML：

<html>
    <head>
        <link rel="stylesheet" type="text/css" href="style.css">
        <title>HTML Library</title>
    </head>
    <body>
        <div id="nav" class="closed">
            <ul>
                <li><a href="index.html"><h1>HOME</h1></a></li>
            </ul>
        </div>
 <button onclick="JavaScript: navtoggle(this);" id="navget">NAV</button>
    </body>
</html>

The JS: JS：

function navtoggle(elementRef){
if (document.getElementById('nav').className = 'closed') 
    {document.getElementById('nav').className = 'open'}

else if (document.getElementById('nav').className = 'open')
    {document.getElementById('nav').className = 'closed'};

}

And the CSS: 和CSS：

.closed {
    display: none;
}

.open {
    display: block;
}

#navget {
    width: 100px; height: 100px;
}

I know that it would be easier to just use a checkbox, and I do know how to do that. 我知道只使用复选框会更容易，而且我确实知道该怎么做。 However, I want it to just be a button so that I can make it look better and such. 但是，我希望它只是一个按钮，这样我才能使其看起来更好。 I'm rather new to JS so please do not be too harsh for the dumb question. 我对JS很陌生，所以请不要对这个愚蠢的问题太苛刻。 Thank you. 谢谢。

Answer 1

in conditional statement you have use "=" instead of compare "==" 在条件语句中，您使用“ =”而不是“ ==“

 if (document.getElementById('nav').className == 'closed') {
    document.getElementById('nav').className = 'open'
  } else if (document.getElementById('nav').className == 'open') {
    document.getElementById('nav').className = 'closed'

Answer 2

you have several problems in your sintax I made you a plunker here so you can see all the details, but basically: 您的sintax有几个问题，我在这里为您提供了一个小工具，因此您可以看到所有详细信息，但基本上是：

function navtoggle(elementRef){
  if (document.getElementById('nav').className === 'closed')  {
    document.getElementById('nav').className = 'open'
  }
  else if (document.getElementById('nav').className === 'open'){
    document.getElementById('nav').className = 'closed'
  } //You was using semicolon here and that wasn't parsing well
}

I don't know if miss to add the script in the header also but let me know if it worked 我不知道是否也想在标题中添加脚本，但请告诉我它是否有效

使用JS if语句通过按钮更改div类（我在做什么错）？

问题描述

2 个解决方案

解决方案1
0 2015-03-31 12:10:31

解决方案2
0 2015-03-31 12:21:09

使用JS if语句通过按钮更改div类（我在做什么错）？

问题描述

2 个解决方案

解决方案1 0 2015-03-31 12:10:31

解决方案2 0 2015-03-31 12:21:09

解决方案1
0 2015-03-31 12:10:31

解决方案2
0 2015-03-31 12:21:09