Question

我希望javascript返回值为'sct'或'rain'（剥离“，20”或“，70”）来自以下网址：

<script>
var urls = [
"https://api.weather.gov/icons/land/day/sct,20?size=medium",
"https://api.weather.gov/icons/land/day/sct?size=medium",
"https://api.weather.gov/icons/land/night/rain?size=medium",
"https://api.weather.gov/icons/land/day/rain,60/rain,70?size=medium"
];
for(var key in urls) {
  console.log(get_icon(urls[key]));
}
function get_icon(text) {
 /* not sure what to do here */
}
</script>

逻辑将在最后一次斜杠之后和逗号或问号之前获取字符串。我正在努力使用正则表达式来做到这一点。

Answer 1

您可以将此正则表达式与.*的贪婪匹配结合使用，以确保匹配上一个/：

/.*\/([^,?]+)/

RegEx Demo

([^,?]+)会在捕获组中的下一个?或,之前为您提供字符串。

<强>代码：

var urls = [
"https://api.weather.gov/icons/land/day/sct,20?size=medium",
"https://api.weather.gov/icons/land/day/sct?size=medium",
"https://api.weather.gov/icons/land/night/rain?size=medium",
"https://api.weather.gov/icons/land/day/rain,60/rain,70?size=medium"
];
for(var key in urls) {
  console.log(get_icon(urls[key]));
}
function get_icon(text) {
  return (text.match(/.*\/([^,?]+)/) || [null][null])[1];
}

Answer 2

请检查此正则表达式。提取第1组：

employees.aggregate(
[{ "$match":
 {"$and": [
   {"$or": [
     {name : { "$regex": param, "$options":"i"}},
     {title : { "$regex": param, "$options":"i"}},
   ]},
   { tenure : true }
]}
},
  {"$sort":{experience : -1}},
  {"$limit" : 100}
])

Answer 3

回复你的需要，我可以这样做：

function get_icon(text) {
   var pos = text.lastIndexOf("/");
   var qmark = text.lastIndexOf("?size");
   var res = text.substring(pos+1, qmark);
   var res = res.split(",");
   if (res.length == 2)
      return res[1];
   else
      return null;
}

Javascript RegEx在斜杠和逗号或问号之间的URL中查找字符串

3 个答案: