Go HTML模板如何从funcMap获取功能中的用户IP

Question

I know how to get the user IP from the *http.Requeststruct:

strings.Split(r.RemoteAddr, ":")[0]

And I know how to define a template.FuncMap:

funcMap = template.FuncMap{                                                           
        // gets the time since the post was posted                                    
        "since": func(t time.Time) string {                                           
                s := time.Since(t).String()                                           
                return strings.Replace(s[:strings.LastIndex(s, "m")+1], "h", "h ", 1) 
        },                                                                            
}                                                                                     

How would I get the users IP from a template function defined in the template.FuncMap?

Answer 1

The func map is intended for helper functions, rather than data, and should be defined once before parsing templates, so this isn't a good place for it. You should instead pass in the data to the view when executing the template.

This would fit better in your data/context for the view. For example if you use a map[string]interface{} for that (one of the few places I'd use interface{}), you can simply assign it there:

userIP := strings.Split(r.RemoteAddr, ":")[0]
data := map[string]interface{}{"userIP":userIP}
err := tmpl.Execute(w,data)

Template:

<p>User IP:{{.userIP}}</p>