NSURL 为有效的 URL 返回 nil

Question

我有 google 地图的有效 URL，如果您在浏览器中运行会显示地图图像。但是，当我将它放入我的 Swift 代码中并尝试从 String 创建一个 NSURL 时，它 returns nil

let urlString = "https://maps.googleapis.com/maps/api/staticmap?maptype=hybrid&center=37.33233141,-122.0312186&path=color:0xff0000|weight:10|37.33233141,-122.0312186|21.422570,%2039.826190&markers=color:blue%7Clabel:S%7C37.33233141,-122.0312186&markers=color:blue%7Clabel:S%7C21.422570,39.826190&zoom=1&size=1080x1920"
let url = NSURL(string: urlString)

目前，这个 returns 没有，我不知道为什么。我做错了什么吗？

Answer 1

它应该有效：这就是为什么 http://www.url-encode-decode.com

        let url = NSURL(string: urlString.stringByAddingPercentEscapesUsingEncoding(NSUTF8StringEncoding)!)

由于上面的 API 已弃用，替代方法是

    let url = NSURL(string: urlString.stringByAddingPercentEncodingWithAllowedCharacters(NSCharacterSet.URLQueryAllowedCharacterSet())!)

Answer 2

查看 Apple documentation:

This method expects URLString to contain only characters that are allowed in a properly formed URL. All other characters must be properly percent escaped. Any percent-escaped characters are interpreted using UTF-8 encoding.

您的字符串中可能存在错误，您需要在将其传递给 NSURL 之前对其进行编码，您可以通过 stringByAddingPercentEncodingWithAllowedCharacters:

进行此操作

if let encodedString = urlString.stringByAddingPercentEncodingWithAllowedCharacters(NSCharacterSet.URLQueryAllowedCharacterSet() {
    url = NSURL(string: urlString)
}

NSURL 为有效的 URL 返回 nil

NSURL is returning nil for a valid URL

nsurl

ios

swift