Color all occurrences of string in swift
Swift 5
let attrStr = NSMutableAttributedString(string: "hi hihi hey")
let inputLength = attrStr.string.count
let searchString = "hi"
let searchLength = searchString.characters.count
var range = NSRange(location: 0, length: attrStr.length)
while (range.location != NSNotFound) {
range = (attrStr.string as NSString).range(of: searchString, options: [], range: range)
if (range.location != NSNotFound) {
attrStr.addAttribute(NSAttributedString.Key.foregroundColor, value: UIColor.yellow, range: NSRange(location: range.location, length: searchLength))
range = NSRange(location: range.location + range.length, length: inputLength - (range.location + range.length))
}
}
Swift 3
let attrStr = NSMutableAttributedString(string: "hi hihi hey")
let inputLength = attrStr.string.characters.count
let searchString = "hi"
let searchLength = searchString.characters.count
var range = NSRange(location: 0, length: attrStr.length)
while (range.location != NSNotFound) {
range = (attrStr.string as NSString).range(of: searchString, options: [], range: range)
if (range.location != NSNotFound) {
attrStr.addAttribute(NSForegroundColorAttributeName, value: UIColor.yellow(), range: NSRange(location: range.location, length: searchLength))
range = NSRange(location: range.location + range.length, length: inputLength - (range.location + range.length))
}
}
Swift 2
let attrStr = NSMutableAttributedString(string: "hi hihi hey")
let inputLength = attrStr.string.characters.count
let searchString = "hi"
let searchLength = searchString.characters.count
var range = NSRange(location: 0, length: attrStr.length)
while (range.location != NSNotFound) {
range = (attrStr.string as NSString).rangeOfString(searchString, options: [], range: range)
if (range.location != NSNotFound) {
attrStr.addAttribute(NSForegroundColorAttributeName, value: UIColor.yellowColor(), range: NSRange(location: range.location, length: searchLength))
range = NSRange(location: range.location + range.length, length: inputLength - (range.location + range.length))
}
}
Swift 4:
let string = "foo fbar foofoo foofo"
let mutableAttributedString = NSMutableAttributedString(string: string)
let searchString = "foo"
var rangeToSearch = string.startIndex..<string.endIndex
while let matchingRange = string.range(of: searchString, options: [], range: rangeToSearch) {
mutableAttributedString.addAttribute(.foregroundColor, value: UIColor.yellow, range: NSRange(matchingRange, in: string))
rangeToSearch = matchingRange.upperBound..<string.endIndex
}