Question on extracting a substring from a url

Question

VolmDev OP

Created Dec ’15

Replies 1

Boosts 0

Participants 2

Could someone please helpe with the following. I am trying to extract a string from a string.

I have the following url: https://api.github.com/gists/public?page=2

How can I cut the portion of the string "?page=2" and store it in a variable so that I would have two parts.

var strBase = https://api.github.com/gists/public"

and the page part

var strPage = "?page=2".

Thanks you.

Dave.

Answered by OOPer in 98836022

Just as a String manipulation:

 var urlStr = "https:...?page=2"
var strBase: String
var strPage: String
if let qIndex = urlStr.characters.indexOf("?") {
    strBase = urlStr.substringToIndex(qIndex)
    strPage = urlStr.substringFromIndex(qIndex)
} else {
    strBase = urlStr
    strPage = ""
}

Or this is another way preferred by many:

 let parts = urlStr.componentsSeparatedByString("?")
strBase = parts[0]
strPage = parts.count >= 2 ? "?" + parts[1] : ""

But if you want manipulate it as URL rather than String, you better consider adopting NSURLComponents.

 if let urlCompo = NSURLComponents(string: urlStr) {
    strPage = urlCompo.query != nil ? "?" + urlCompo.query! : ""
    urlCompo.query = nil
    strBase = urlCompo.string!
} else {
    fatalError("invalid URL")
}

Boost

Answer 1

OOPer OP

Dec ’15

Accepted Answer

Just as a String manipulation:

 var urlStr = "https:...?page=2"
var strBase: String
var strPage: String
if let qIndex = urlStr.characters.indexOf("?") {
    strBase = urlStr.substringToIndex(qIndex)
    strPage = urlStr.substringFromIndex(qIndex)
} else {
    strBase = urlStr
    strPage = ""
}

Or this is another way preferred by many:

 let parts = urlStr.componentsSeparatedByString("?")
strBase = parts[0]
strPage = parts.count >= 2 ? "?" + parts[1] : ""

But if you want manipulate it as URL rather than String, you better consider adopting NSURLComponents.

 if let urlCompo = NSURLComponents(string: urlStr) {
    strPage = urlCompo.query != nil ? "?" + urlCompo.query! : ""
    urlCompo.query = nil
    strBase = urlCompo.string!
} else {
    fatalError("invalid URL")
}

0

	var urlStr = "https:...?page=2"
	var strBase: String
	var strPage: String
	if let qIndex = urlStr.characters.indexOf("?") {
	strBase = urlStr.substringToIndex(qIndex)
	strPage = urlStr.substringFromIndex(qIndex)
	} else {
	strBase = urlStr
	strPage = ""
	}

	let parts = urlStr.componentsSeparatedByString("?")
	strBase = parts[0]
	strPage = parts.count >= 2 ? "?" + parts[1] : ""

	if let urlCompo = NSURLComponents(string: urlStr) {
	strPage = urlCompo.query != nil ? "?" + urlCompo.query! : ""
	urlCompo.query = nil
	strBase = urlCompo.string!
	} else {
	fatalError("invalid URL")
	}