为什么我的String比较在iOS 6中不起作用？ [英] Why isn't my String comparison working in iOS 6?

问题描述

可能重复：

了解Objective-C中的NSString比较

I已经将这个简单的代码用于应用程序的多个版本，直到iOS 6字符串比较已经有效，但现在它失败了 - 为什么？

I've used this simple code for several releases of an app, and until iOS 6 the string comparison has worked but now it fails -Why?

if(selectedCell.textLabel.text==@"Font"){
    NSLog(@"going to dofontpicker");
    [self doFontPicker];
}else if(selectedCell.textLabel.text==@"Color"){
    NSLog(@"going to do colorpicker");
    [self doColorPicker];
}

推荐答案

因为它从未真正起作用。使用 == 运算符比较字符串不起作用，因为字符串（NSString对象）是指针 - 进行数字比较只比较它们的地址，而不是它们的内容。你需要写

Because it never really worked. Comparing strings doesn't work using the == operator, since strings (NSString objects) are pointers - doing a numerical comparison only compares their address, not their contents. You need to write

if ([someString isEqualToString:@"Font"]) {
    // do stuff
}

编辑：我听到你尖叫但它确实有效！它真的有效，直到iOS 6 ！ - 不。它没有，这只是偶然的事情。

I hear you screaming "But it worked! It really worked until iOS 6!" - Nope. It didn't, it was just something accidental.

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