斯威夫特是否会通过声明落空?例如,如果我做以下
var testVar = "hello"
var result = 0
switch(testVal)
{
case "one":
result = 1
case "two":
result = 1
default:
result = 3
}
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是否可以为案例"一"和案例"两个"执行相同的代码?
我正在使用此代码从十六进制值创建UIColor.它的工作完美.
extension UIColor {
convenience init(red: Int, green: Int, blue: Int) {
assert(red >= 0 && red <= 255, "Invalid red component")
assert(green >= 0 && green <= 255, "Invalid green component")
assert(blue >= 0 && blue <= 255, "Invalid blue component")
self.init(red: CGFloat(red) / 255.0, green: CGFloat(green) / 255.0, blue: CGFloat(blue) / 255.0, alpha: 1.0)
}
convenience init(netHex:Int) {
self.init(red:(netHex >> 16) & 0xff, green:(netHex >> 8) & 0xff, blue:netHex & 0xff)
}
}
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用法:
var textColor = UIColor(netHex: …Run Code Online (Sandbox Code Playgroud)