GoLang-具有HTML的XmlPath选择器

I am looking at the documented example here, but it is iterating purely over an XML tree, and not HTML. Therefore, I am still partly confused.

For example, if I wanted to find a specific meta tag within the head tag by name, it seems I cannot? Instead, I need to find it by the order it is in the head tag. In this case, I want the 8th meta tag, which I assume is:

headTag, err := getByID(xmlroot, "/head/meta[8]/")

But of course, this is using a getByID function for a tag name - which I don't believe will work. What is the full list of "getBy..." commands?

Then, the problem is, how do I access the meta tag's contents? The documentation only provides examples for the inner tag node content. However, will this example work?:

resp.Query = extractValue(headTag, @content)

The @ selector confuses me, is this appropriate for this case?

In other words:

1. Is there a proper HTML example available?
2. Is there a list of correct selectors for IDs, Tags, etc?
3. Can Tags be found by name, and content extracted from its inner content tag?

Thank you very much!

XPath does not seem suitable here; you should be using goquery, which is designed for HTML.

Here is an example:

package main

import (
    "fmt"

    "github.com/PuerkitoBio/goquery"
)

func main() {
    doc, err := goquery.NewDocument("https://example.com")
    if err != nil {
        panic(err)
    }
    s := doc.Find(`html > head > meta[name="viewport"]`)
    if s.Length() == 0 {
        fmt.Println("could not find viewpoint")
        return
    }
    fmt.Println(s.Eq(0).AttrOr("content", ""))
}

I know this answer is late, but I still want to recommend an htmlquery package that is simple and powerful, based on XPath expressions*.

The below code based on @Time-Cooper example.

package main

import (
    "fmt"

    "github.com/antchfx/htmlquery"
)

func main() {
    doc, err := htmlquery.LoadURL("https://example.com")
    if err != nil {
        panic(err)
    }
    s := htmlquery.Find(doc, "//meta[@name='viewport']")
    if len(s) == 0 {
        fmt.Println("could not find viewpoint")
        return
    }
    fmt.Println(htmlquery.SelectAttr(s[0], "content"))

    // alternative method,but simple more.
    s2 := htmlquery.FindOne(doc, "//meta[@name='viewport']/@content")
    fmt.Println(htmlquery.InnerText(s2))
}