如何从NSDictionary获取密钥对象？ [英] How to get object for key from NSDictionary?

问题描述

在名为 dict 的词典中，键值对是：

In dictionary named dict the key value pair is:

alba \ U2019s window=westindies中的模型。;

"alba\U2019s window" = "A model in westindies.";

并发送 objectForKey：我得到的字符串就像alba的窗口。当我发送如下内容时：

And to send objectForKey: I am getting the string like "alba's window". When I send like following:

[dict objectForKey：alba的窗口];

[dict objectForKey:alba's window];

我没有得到任何东西，它显示为空。

I am not getting anything, it is showing null.

推荐答案

对于初学者，你可能会想要使它成为一个实际的字符串，如下所示：

For starters, you might want to make that an actual string, like so:

[dict objectForKey:@"alba's window"];

另请注意 \ U2019 不是 ;但'，完全是另一个角色。

Note also that \U2019 is not '; but ’, which is a different character entirely.

更一般地说，坚持字典键的[a-zA-Z0-9] + 可能是一个好主意，除非您使用与键完全相同的字符串以编程方式插入和检索。

And more generally, sticking to [a-zA-Z0-9]+ for dictionary keys is probably a good idea, unless you are inserting and retrieving programmatically using the exact same string as a key.

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