xcode 'NSDate' 没有可见的 @interface 声明了选择器 'initWithString:'
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No visible @interface for 'NSDate' declares the selector 'initWithString:'
提问by sergtk
Possible Duplicate:
NSDate initWithString
I wrote the following line of code:
我写了以下代码行：
[[NSDate alloc] initWithString:@"2013-03-24 10:45:32 +0200"];
When I try to compile I obtain the following error message:
当我尝试编译时，我收到以下错误消息：
ARC Semantic Issue: No visible @interface for 'NSDate' declares the selector 'initWithString:'
ARC 语义问题：“NSDate”没有可见的 @interface 声明选择器“initWithString:”
In project there is following include:
在项目中有以下内容：
#import <Foundation/Foundation.h>
To be sure that class is included, I tried following line which is compiled without issues:
为了确保包含该类，我尝试了以下编译没有问题的行：
[[NSDate alloc] init];
What is wrong with my code?
我的代码有什么问题？
XCode version 4.6.
Base SDK in project iOS 6.1.
XCode 4.6 版。
项目 iOS 6.1 中的基础 SDK。
回答by Dhruv Goel
initWithString function is not present in NSDate class for iOS Platforms, since you'll need to first specify a date formatter using NSDateFormatter which converts textual representations of dates and times into NSDate objects. Use something like this :
initWithString 函数在 iOS 平台的 NSDate 类中不存在，因为您需要首先使用 NSDateFormatter 指定一个日期格式化程序，它将日期和时间的文本表示形式转换为 NSDate 对象。使用这样的东西：
NSString *currentDateString = @"2013-03-24 10:45:32";
NSDateFormatter *dateFormater = [[NSDateFormatter alloc] init];
[dateFormater setDateFormat:@"yyyy-MM-DD HH:mm:ss"];
NSDate *currentDate = [dateFormater dateFromString:currentDateString];
