ios 将可选字符串转换为日期
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Convert Optional string to date
提问by WDFAN23
I have this Optional(2015-07-27 19:29:50 +0000)as a string? and I want to convert it to a date (NSDate) but I can't figure it out I've been searching a lot for solutions but I am pretty new to coding so if anyone could help I would appreciate it.
我有这个Optional(2015-07-27 19:29:50 +0000)字符串？我想将它转换为日期（NSDate），但我无法弄清楚我一直在寻找解决方案，但我对编码很陌生，所以如果有人能帮助我，我将不胜感激。
This is what I am using to convert the string to a date currently.
这是我当前用来将字符串转换为日期的方法。
note: dateString is Optional(2015-07-27 19:29:50 +0000)
注意：日期字符串是 Optional(2015-07-27 19:29:50 +0000)
dateFormatter = NSDateFormatter()
println(dateFormatter)
dateFormatter.dateFormat = "yyyy-MM-dd"
let s = dateFormatter.dateFromString(dateString)
I always get a nil value
我总是得到一个零值
回答by MirekE
If you are getting nil from NSDateFormatter, you likely specified incorrect date format. Try this:
如果您从 NSDateFormatter 得到 nil，则您可能指定了不正确的日期格式。尝试这个：
let strTime = "2015-07-27 19:29:50 +0000"
let formatter = NSDateFormatter()
formatter.dateFormat = "yyyy-MM-dd HH:mm:ss Z"
formatter.dateFromString(strTime) // Returns "Jul 27, 2015, 12:29 PM" PST
回答by Good Doug
You will want to use a NSDateFormatterand call dateFromString:on it to get the date from the string. See Apple's NSDateFormatter documentationfor a great explanation of doing what you want.
您将需要使用 aNSDateFormatter并调用dateFromString:它以从字符串中获取日期。请参阅Apple 的 NSDateFormatter 文档以获取有关执行所需操作的详细说明。
回答by Muthama Kahohi
In swift 3.0:
在 Swift 3.0 中：
let strTime = "2015-07-27 19:29:50 +0000"
let formatter = NSDateFormatter()
formatter.dateFormat = "yyyy-MM-dd HH:mm:ss Z"
formatter.date(from: strTime)
回答by shiva
dateString is already date and need to convert to string. Below code is working fine
dateString 已经是日期，需要转换为字符串。下面的代码工作正常
dateFormatter = NSDateFormatter() println(dateFormatter) dateFormatter.dateFormat = "yyyy-MM-dd" let s = dateFormatter.string(from: dateString)
dateFormatter = NSDateFormatter() println(dateFormatter) dateFormatter.dateFormat = "yyyy-MM-dd" let s = dateFormatter.string(from: dateString)
