你可以尝试这样的事情:
编辑:包括 toHex(alpha:),来自我多年前可能从网络上得到的代码。
EDIT3,4:包括 #RRGGBBAA 的情况
编辑5:去除十六进制字符串中的空格,以使 NSColor (十六进制:“# 2196f380”)也能工作。
extension NSColor {
convenience init(hex: String) {
let trimHex = hex.trimmingCharacters(in: .whitespacesAndNewlines)
let dropHash = String(trimHex.dropFirst()).trimmingCharacters(in: .whitespacesAndNewlines)
let hexString = trimHex.starts(with: "#") ? dropHash : trimHex
let ui64 = UInt64(hexString, radix: 16)
let value = ui64 != nil ? Int(ui64!) : 0
// #RRGGBB
var components = (
R: CGFloat((value >> 16) & 0xff) / 255,
G: CGFloat((value >> 08) & 0xff) / 255,
B: CGFloat((value >> 00) & 0xff) / 255,
a: CGFloat(1)
)
if String(hexString).count == 8 {
// #RRGGBBAA
components = (
R: CGFloat((value >> 24) & 0xff) / 255,
G: CGFloat((value >> 16) & 0xff) / 255,
B: CGFloat((value >> 08) & 0xff) / 255,
a: CGFloat((value >> 00) & 0xff) / 255
)
}
self.init(red: components.R, green: components.G, blue: components.B, alpha: components.a)
}
func toHex(alpha: Bool = false) -> String? {
guard let components = cgColor.components, components.count >= 3 else {
return nil
}
let r = Float(components[0])
let g = Float(components[1])
let b = Float(components[2])
var a = Float(1.0)
if components.count >= 4 {
a = Float(components[3])
}
if alpha {
return String(format: "%02lX%02lX%02lX%02lX", lroundf(r * 255), lroundf(g * 255), lroundf(b * 255), lroundf(a * 255))
} else {
return String(format: "%02lX%02lX%02lX", lroundf(r * 255), lroundf(g * 255), lroundf(b * 255))
}
}
}
let nscol = NSColor(hex: "#2196f3") // <-- with or without #
EDIT2:
您可以对 UIColor 和 Color (使用 UIColor 或 NSColor)执行相同的操作:
extension Color {
public init(hex: String) {
self.init(UIColor(hex: hex))
}
public func toHex(alpha: Bool = false) -> String? {
UIColor(self).toHex(alpha: alpha)
}
}