ios - stringByAddingPercentEscapesUsingEncoding(NSUTF8StringEncoding) returns Optional in Swift -

ios - stringByAddingPercentEscapesUsingEncoding(NSUTF8StringEncoding) returns Optional in Swift -

i trying solve next issues using swift:

1) optional? instead of returning "1%20market%20street,%20san%20francisco,%20ca%2094107" like, why next code returning "optional("1%20market%20street,%20san%20francisco,%20ca%2094107")"

println("\(address.stringbyaddingpercentescapesusingencoding(nsutf8stringencoding))")

2) how replace commas %2c?

you can utilize

allow tempstring: string? = "1%20market%20street,%20san%20francisco,%20ca%2094107" if tempstring != nil { allow newstring = tempstring!.stringbyreplacingoccurrencesofstring(",", withstring: "%2c", options: nsstringcompareoptions.literalsearch, range: nil) }

it returns optional,because method homecoming nil.

ios swift