ios 如何在 iphone 中获取 NSMutableDictionary 计数？
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How to get NSMutableDictionary count in iphone?
提问by Gopinath
I want to get NSMutableDictionary count in iphone. I want to know how many items are in NSMutableDictionry. I tried these code to find out the solution but, not helped me lot.
我想在 iphone 中获得 NSMutableDictionary 计数。我想知道 NSMutableDictionry 中有多少项。我尝试了这些代码来找出解决方案，但对我没有多大帮助。
NSLog(@"Count : %d", [mutableDictionary count]);
It is always returns '0'. How to get the count of NSMutableDictionary in iPhone? Thanks in advance.
它总是返回“0”。如何在 iPhone 中获取 NSMutableDictionary 的数量？提前致谢。
回答by Jesse Black
You can find out how many key-object (key-value) pairs there are like so:
您可以像这样找出有多少键-对象（键-值）对：
NSArray * allKeys = [mutableDictionary allKeys];
NSLog(@"Count : %d", [allKeys count]);
EDIT
编辑
Upon looking through the dictionary documentation, NSDictionary's countmethod (or property) should work as well. I think you may have been receiving 0 count because the dictionary was empty or nil. I offered my solution because I tend to care more about enumerating the keys than counting the entries directly.
查看字典文档后，NSDictionary的count方法（或属性）也应该有效。我认为您可能已经收到 0 计数，因为字典是空的或为零。我提供了我的解决方案，因为我更关心枚举键而不是直接计算条目。
Please consider the fact that you fixed the issue somewhere else.
? By actually populating the dictionary
or
? By fixing a bug where mutableDictionary was somehow nil
请考虑您已在其他地方解决了该问题。
? 通过实际填充字典
或
？通过修复 mutableDictionary 以某种方式为零的错误
I run this test code and get the commented output
我运行此测试代码并获得注释输出
NSMutableDictionary * countDict = [NSMutableDictionary dictionaryWithObject:@"test" forKey:@"test"];
[countDict setObject:@"foo" forKey:@"bar"];
NSLog(@"test count %d", countDict.count); //test count 2
countDict = nil;
NSLog(@"test count %d", countDict.count); //test count 0
回答by Ankit Srivastava
[[dictionary allKeys] count];will do the trick.
[[dictionary allKeys] count];会做的伎俩。
回答by Rakesh Bhatt
NSMutableDictionary *dict = [NSMutableDictionary dictionaryWithObjectsAndKeys:@"Rakesh",@"Name",@"[email protected]",@"Email",nil];
NSLog(@"Count : %d", [dict count])
Try this
尝试这个
回答by Sid
if you looking to count NSMutableDictionary values for any Array item you can use.
如果您想为您可以使用的任何 Array 项目计算 NSMutableDictionary 值。
NSLog(@"myDictionaryCount %lu", (unsigned long)[myDictionary[@"items"] count]);
