How can I concatenate NSAttributedStrings?

Question

I need to search some strings and set some attributes prior to merging the strings, so having NSStrings -> Concatenate them -> Make NSAttributedString is not an option, is t

Answer 1

2020 | SWIFT 5.1:

You're able to add 2 NSMutableAttributedString by the following way:

let concatenated = NSAttrStr1.append(NSAttrStr2)

Another way works with NSMutableAttributedString and NSAttributedString both:

[NSAttrStr1, NSAttrStr2].joinWith(separator: "")

---

Another way is....

var full = NSAttrStr1 + NSAttrStr2 + NSAttrStr3

and:

var full = NSMutableAttributedString(string: "hello ")
// NSAttrStr1 == 1


full += NSAttrStr1 // full == "hello 1"       
full += " world"   // full == "hello 1 world"

You can do this with the following extension:

// works with NSAttributedString and NSMutableAttributedString!
public extension NSAttributedString {
    static func + (left: NSAttributedString, right: NSAttributedString) -> NSAttributedString {
        let leftCopy = NSMutableAttributedString(attributedString: left)
        leftCopy.append(right)
        return leftCopy
    }

    static func + (left: NSAttributedString, right: String) -> NSAttributedString {
        let leftCopy = NSMutableAttributedString(attributedString: left)
        let rightAttr = NSMutableAttributedString(string: right)
        leftCopy.append(rightAttr)
        return leftCopy
    }

    static func + (left: String, right: NSAttributedString) -> NSAttributedString {
        let leftAttr = NSMutableAttributedString(string: left)
        leftAttr.append(right)
        return leftAttr
    }
}

public extension NSMutableAttributedString {
    static func += (left: NSMutableAttributedString, right: String) -> NSMutableAttributedString {
        let rightAttr = NSMutableAttributedString(string: right)
        left.append(rightAttr)
        return left
    }

    static func += (left: NSMutableAttributedString, right: NSAttributedString) -> NSMutableAttributedString {
        left.append(right)
        return left
    }
}