解决NSData转NSString返回nil的问题
// 字符串转DataNSString *str =@"jesfds";NSData *data =[str dataUsingEncoding:NSUTF8StringEncoding];//NSData 转NSStringNSString *result =[[ NSString alloc]...
从iPhone相机获取图像路径使用UIImagePickerController返回nil
I am trying to get the image path from camera using UIImagePickerController 我试图使用UIImagePickerController从相机获取图像路径 here is the code : 这是代码: @IBAction...
控制台错误:UICollectionView必须使用非nil布局参数初始化。
I'm new to UICollectionView and I'm following a tutorial that I found on Youtube, but i'm stuck on an error I can't figure out. 我是UICollectionView新手,我...
在打开实际具有值的可选项时打开Nil
I'm getting a very weird error, while unwrapping an optional. When I print the value, I can actually see it but yet, it crashes and it says: 我解决了一个非常...
应用程序保持崩溃发现Nil Swift
I am trying to display a webview in my app. The url for the webview is in object format because i got it from json. So in my code i converted the obje...
我怎样才能避免最后打印的nil呢?
I have coded this function that prints-out the state of the board, but in the end, due to the fact that there isnt no return the function prints an ni...
Getting undefined method `+' for nil:NilClass only with RubyMine debugger on
My environment: 我的环境: Ubuntu 14Ruby 2.2.1Rails 4.2 Newly created rails application, with 1 action: 新创建的rails应用程序,具有1个操作: class FramesController < A...
在objective C中字符串值总是显示为nil。
I have upgraded to Xcode 5.0. And when I run an app in debug mode and try to print an NSString value in console, it gives me the below error. Any idea...
swift中的nil与Objective-C中的nil区别
1.OC中,只有对象才能设置为nil,而swift中除了对象,Int、struct、enum等任何可选类型都可以等于nil2.OC中,nil是一个指向不存在对象的指针。swift中,nil不是指针,nil是个确定的值,用来表示值缺失。...
Objective-c:当键存在时,自定义类实例作为字典键返回nil
I have a custom class I'm using instances of as keys in a dictionary. The problem is, sometimes (not all the time) requesting a value from a dictionar...
在Swift Class中访问Objective C AppDelegate String返回nil
I'm attempting to access a NSNumber value from my ObjectiveC AppDelegate in/using a Swift class however it continuously returns nil on the Swift side ...
Swift String附加可选的nil
The second way of printing an optional value is correct, but is there any shorter way to write code with the same effect? I.e. Where before unwrapping...
【原创】大叔问题定位分享(36)openresty(nginx+lua)中获取不到post数据,ngx.req.get_body_data返回nil
openresty(nginx+lua)中获取不到post数据,ngx.req.get_body_data返回nil This function returns nil if the request body has not been read, the request body has been...
Lisp:从列表中删除尾随nil的优雅方式? (评论)
I want to write a function that removes trailing nil's from a list. I first tried to write it elegantly with recursion, but ended up like this: 我想编写一个...
【转】self.myOutlet=nil、viewDidUnload、dealloc的本质剖析
对于iphone开发人员来说,内存管理是极为重要的技巧,哪怕程序的功能再强大,设计再漂亮,如果内存控制不好,也难逃程序莫名退出的噩运,这与网页开发是完全不同的。内存控制里面有很多门道,在这里分析一下 viewDidUnload 和 dealloc 的区别,关于这两者的区别的文章很多,但是大都是摘抄和...
[转]一个小试验验证对象的指针计数置为nil的情况
本文转载于新风作浪的博客专栏,博客地址:http://blog.csdn.net/duxinfeng2010/article/details/8757211以下博客原文:最近遇到这样一个问题,以前的时候并未注意;新建一个工程,然后添加一个类,文件结构是这样的然后写了这样一小段程序,运行- (void...
nil的未定义方法`errors':传递User对象时的NilClass
My application has user accounts and the users can log in to view the application. When a user is created by an admin a random password is generated a...
将nil对象传递给函数
I was wondering if objective C does any check to see if a pointer to an object is nil before calling the function. 我想知道在调用函数之前,目标C是否进行任何检查以查看指向对象的指针是否...
weak属性需要在dealloc中置nil么?
出题者简介: 孙源(sunnyxx),目前就职于百度整理者简介:陈奕龙(子循),目前就职于滴滴出行。转载者:豆电雨(starain)微信:doudianyu不需要。在ARC环境无论是强指针还是弱指针都无需在 dealloc 设置为 nil , ARC 会自动帮我们处理即便是编译器不帮我们做这些,we...
如何在Swift中检查Generic类型是否为nil
I'm trying to copy the all function from python to swift, starting off with checking for any nill items in a list, but I'm having a tough time checkin...