ios 带有 OR 条件的 Objective-C IF 语句
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Objective-C IF statement with OR condition
提问by Alberto Schiariti
What's wrong in this IF statement?
这个 IF 语句有什么问题？
if ([currentElement isEqualToString:@"aaa" || currentElement isEqualToString:@"bbb"])
XCode says:
XCode 说：
No visible @interface for 'NSString' declares the selector 'isEqualToString:isEqualToString:'
I'm into an NSXML Parser procedure if it can help, but I think it's not that the problem.
如果有帮助，我会使用 NSXML Parser 程序，但我认为这不是问题所在。
回答by Vladimir
You must compare result of two method calls:
您必须比较两个方法调用的结果：
if ([currentElement isEqualToString:@"aaa"] || [currentElement isEqualToString:@"bbb"])
The code you have actually compiles as
您实际编译的代码为
if ([currentElement isEqualToString:(@"aaa"||currentElement) isEqualToString:@"bbb"])
that is compiler tries to call non-existing isEqualToString:isEqualToString:method of NSString
那是编译器试图调用isEqualToString:isEqualToString:NSString 的不存在的方法
