我写了两个函数给String添加下划线并删除下划线:
我想用按钮切换下划线。 那么我该如何检查NSMutableAttributedString是否具有下划线属性:
func addUlnTxtFnc(TxtPsgVal :String) -> NSMutableAttributedString
{
let TxtRngVal = NSMakeRange(0, TxtPsgVal.characters.count)
let TxtUnlVal = NSMutableAttributedString(string: TxtPsgVal)
TxtUnlVal.addAttribute(NSUnderlineStyleAttributeName, value:NSUnderlineStyle.StyleSingle.rawValue, range: TxtRngVal)
return TxtUnlVal
}
func rmvUlnTxtFnc(TxtPsgVal :NSMutableAttributedString) -> NSMutableAttributedString
{
let TxtRngVal = NSMakeRange(0, TxtPsgVal.string.Len())
TxtPsgVal.removeAttribute(NSUnderlineStyleAttributeName, range: TxtRngVal)
return TxtPsgVal
}
答案 0 :(得分:2)
您可以通过调用.enumerateAttribute(attrName:, inRange:, options:, usingBlock:)
上的函数NSMutableAttributedString
作为参数进行检查:
func rmvUlnTxtFnc(TxtPsgVal: NSMutableAttributedString) -> NSMutableAttributedString {
let TxtRngVal = NSMakeRange(0, TxtPsgVal.length)
TxtPsgVal.enumerateAttribute(NSUnderlineStyleAttributeName, inRange: TxtRngVal, options: .LongestEffectiveRangeNotRequired) { attribute, range, pointer in
if attribute != nil {
TxtPsgVal.removeAttribute(NSUnderlineStyleAttributeName, range: range)
}
}
return TxtPsgVal
}
此外,您可以将第一个功能缩短为一行:
func addUlnTxtFnc(TxtPsgVal: String) -> NSMutableAttributedString {
return NSMutableAttributedString(string: TxtPsgVal, attributes: [NSUnderlineStyleAttributeName: NSUnderlineStyle.StyleSingle.rawValue])
}
顺便说一句,您的代码不符合Swift社区提出的Swift style guidelines。