用golang代理的变量替换字符串[关闭]

Question

I'm trying to use the http proxy code here

proxyUrl := url.Parse(strings.Replace("%v", RandomProxyAddress()))
http.DefaultTransport = &http.Transport{Proxy: http.ProxyURL(proxyUrl)}

Tells me there are too many arguments in the url.Parse

But when I try

proxyUrl := url.Parse(RandomProxyAddress())
http.DefaultTransport = &http.Transport{Proxy: http.ProxyURL(proxyUrl)}

I get ./main.go:138: multiple-value url.Parse() in single-value context

When I tried a string replace it also tells me too many varibles. Not sure how to get my proxy to work with the url.Parse

Answer 1

Firstly, url.Parse returns two variables, a URL and an error, as per the docs here.

Secondly, instead of strings.Replace you probably meant to use fmt.Sprintf("%v", RandomProxyAddress()), assuming RandomProxyAddress() returns a string, or something that formats into the string you want. So all in all, you should have:

addr := fmt.Sprintf("%v", RandomProxyAddress())
proxyURL, err := url.Parse(addr)
if err != nil {
    log.Println(err)
}

That said, the fmt.Sprintf would be unnecessary if RandomProxyAddress() already returns a string. Check the docs for fmt and fmt.Sprintf. And if you really did mean to use strings.Replace, notice that it requires four arguments, not two.