cocoa - characterAtIndex 转换为 NSString

Question

我收到错误消息 Incompatible integer to pointer conversion sending 'unichar' (aka 'unsigned short') to parameter of type 'NSString *'在此代码的最后一行。

NSMutableString *sp = [[NSMutableString alloc] initWithString:@"             "];
NSArray *deals=@[@[sp, sp, sp, sp], @[sp, sp, sp, sp]];
NSString* suits = @"NESW";
[deals[0][3] replaceCharactersInRange:NSMakeRange(1, 1) withString:[suits characterAtIndex:2]];

Answer 1

正如错误所述，characterAtIndex: 返回一个 unichar，而 replaceCharactersInRange:withString: 需要一个 NSString。如果您想要一个包含索引 2 处字符的 NSString，请尝试使用 substringWithRange:NSMakeRange(2,1)。