我有一个HTML和JS文件。如果用户想覆盖外部JS文件中声明的默认设置,他们要做的就是将以下内容作为内联脚本包括在内:
<script>
userControls = {
transition : 'fade',
nextText : 'Next'
}
</script>
我面临的问题是我的外部脚本未使用用户设置,而是将所有内容都设置为默认设置。
var defControls = {
transition : 'default',
nextText : 'Next »'
};
var userControls = {};
// CHECKS FOR userControls
if (Object.getOwnPropertyNames(userControls).length > 0) {
var controls = Object.assign({}, defControls, userControls);
} else {
controls = defControls;
}
console.log(userControls);
console.log(controls);
console.log(defControls);
<!DOCTYPE html>
<html>
<head>
<link type="text/css" rel="stylesheet" href="styles.css">
<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<!-- EXTERNAL SCRIPT THAT ACCEPTS USER'S NEW SETTINGS -->
<script type="text/javascript" src="script.js"></script>
</head>
<body>
<!-- SENDS THE NEW PARAMETERS TO script.js -->
<script>
userControls = {
transition : 'fade',
nextText : 'Next'
}
</script>
</body>
</html>
答案 0 :(得分:0)
这是因为您在加载js文件后插入了用户选择。首先要通过以下控制
if (Object.getOwnPropertyNames(userControls).length > 0)
,因此它将始终计算为false
。这就是为什么您不断获得默认值的原因。您应该先插入用户选择脚本,或者在js文件中插入一些异步功能。
答案 1 :(得分:0)
您的代码有四个半错误:
var userControls = {transition: 'fade', nextText: 'Next'};
的内联脚本。并且不要忘了;
最后(这是半个错误)。var userControls = {};
已覆盖内联脚本中的userControls
中的设置。我想您想改写var controls = {};
。var controls = {};
语句之前编写if...else
。console.log(userControls);
而不是console.log(JSON.stringify(userControls));
,您的代码只能从IE的开发人员控制台中写入[object Object]
。但是在Chrome中,它还不错。具有更正代码的解决方案
<!DOCTYPE html>
<html><head>
<!--
<link type="text/css" rel="stylesheet" href="styles.css">
<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
-->
<!-- SENDS THE NEW PARAMETERS TO script.js -->
<script type="text/javascript">
var userControls =
{
transition : 'fade',
nextText : 'Next'
};
</script>
<!-- EXTERNAL SCRIPT THAT ACCEPTS USER'S NEW SETTINGS
src="script.js" -->
<script type="text/javascript">
var defControls =
{
transition : 'default',
nextText : 'Next »'
};
//THIS WAS THE MISTAKE: var userControls = {}; this line has overwrited the settings
var controls = {};
// CHECKS FOR userControls
if(Object.getOwnPropertyNames(userControls).length > 0)
{
controls = Object.assign({}, defControls, userControls);
}
else
{
controls = defControls;
}
console.log('userControls =\n' + JSON.stringify(userControls, null, '\t'));
console.log('controls =\n' + JSON.stringify(controls, null, '\t'));
console.log('defControls =\n' + JSON.stringify(defControls, null, '\t'));
</script>
</head>
<body></body>
</html>