如何遍历正则表达式匹配组

Question

say my data looks like this:

name=peter 
age=40
id=99

I can create a regex

(\w+)=(\w+)

To match name, age, and id into group1, and peter, 40, 99 into group two. However, I want to iterate and even selectively iterate through these groups. E.g.,

I want to do different processing if the group1 value is id. So the algorithm is like

//iterate through all the group1, if I see group1 value is "id", then I assign the corresponding group2 key to some other variable. E.g., newVar = 99

The second thing I want to do is to just jump to the third instance of the matching group1 and get the key "id" out instead of iterating.

Answer 1

Use FindAllStringSubmatch to find all the matches:

pat := regexp.MustCompile(`(\w+)=(\w+)`)
matches := pat.FindAllStringSubmatch(data, -1) // matches is [][]string

Iterate through the matched groups like this:

for _, match := range matches {
    fmt.Printf("key=%s, value=%s
", match[1], match[2])
}

Check for "id" by comparing with match[1]:

for _, match := range matches {
    if match[1] == "id" {
        fmt.Println("the id is: ", match[2])
    }
}

Get the third match by indexing:

match := matches[2] // third match
fmt.Printf("key=%s, value=%s
", match[1], match[2])

playground example