ios - 尝试在 Swift 中使用 unicode 字符定义自定义 NSCharacterSet

Question

我想在 Swift 中定义一个NSCharacterSet包含：[Ａ-Ｚ]（注意双字节，这不是 [AZ]）。

这样做的正确语法是什么？下面我在 Objectiv C 中工作的代码似乎并不那么容易转换为 Swift。

    NSRange alphaDoubleByteRange;
    NSMutableCharacterSet *alphaDoubleByteLetters;
    alphaDoubleByteRange.location = (unsigned int)[@"Ａ" characterAtIndex:0];
    alphaDoubleByteRange.length = 26;
    alphaDoubleByteLetters = [[NSMutableCharacterSet alloc] init];
    [alphaDoubleByteLetters formUnionWithCharacterSet:[NSCharacterSet characterSetWithRange:alphaDoubleByteRange]];
    // Now alphaDoubleByteLetters contains what I want.

Answer 1

您可以从 unicode 标量值的范围创建字符集：

let firstCode = Int("Ａ".unicodeScalars.first!.value)
let lastCode =  Int("Ｚ".unicodeScalars.first!.value)
let alphaDoubleByteRange = NSRange(location: firstCode, length: lastCode - firstCode + 1)
let alphaDoubleByteLetters = NSCharacterSet(range: alphaDoubleByteRange)

或者，在Unicode 表中查找字符并直接使用标量值：

let firstCode = 0xFF21  // "Ａ"
let lastCode =  0xFF3A  // "Ｚ"
// ...