我正在尝试将字符串转换为CGFloat个数字。
如果等于0，我的代码会删除最后一位数字。
如何防止删除零？
let str = "17.30"
let flt = CGFloat((str as NSString).doubleValue) + 2.0
print(flt) // 19.3 -- should be 19.30
答案 0 :(得分：4)
CGFloat无法做到这一点，将浮动转换回String
print(String(format: "%.2f", flt)) // 19.30
答案 1 :(得分：1)
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只是一个数字（因此CGFloat和17.3的值相同）;您真正关心的是如何设置17.30号码的String表示。
作为@vadian解决方案的替代方案，您可以使用CGFloat，如下所示
NSNumberFormatter答案 2 :(得分：0)
适用于swift 4
尝试以NumberFormatter格式使用.decimal：
让text =＆＃34; 123456.789＆＃34;
let formatter = NumberFormatter()
formatter.numberStyle = .decimal
formatter.maximumFractionDigits = 2
let value = formatter.string(from: text! as NSNumber)!
print(value)
Output: 123,456.78