ios ios编程 - 格式字符串未使用数据参数
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ios programming - Data argument not used by format string
提问by gadgetmo
I get a Data argument not used by format stringerror when I run the following code:
Data argument not used by format string运行以下代码时出现错误：
- (void)pickerView:(UIPickerView *)thePickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component {
NSString *colour = ([colourArray objectAtIndex:row]);
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
[defaults setObject:(colour) forKey:@"colour"];
NSLog(@"NSString =", colour);
NSLog(@"NSUserDefaults =", [defaults objectForKey:@"colour"]);
}
I get the error on both NSLoglines. Also, here is what the log says:
我在两条NSLog线上都收到错误消息。另外，这里是日志所说的：
2011-10-25 09:01:50.260 Random[35636:b303] NSString =
2011-10-25 09:01:50.260 Random[35636:b303] NSUserDefaults =
Thank you, Arthur
谢谢你，亚瑟
回答by zakishaheen
NSLog(@"NSString = ", colour);
NSLog(@"NSUserDefaults =", [defaults objectForKey:@"colour"]);
Is problematic
有问题
Should be
应该
NSLog(@"NSString = %@", colour);
NSLog(@"NSUserDefaults = %@", [defaults objectForKey:@"colour"]);
The format specifier in this case is the %@which is used to print an object. To print numbers you'd use something like %d. See complete documentation here.
在这种情况下，格式说明符%@是用于打印object. 要打印数字，您可以使用类似%d. 在此处查看完整文档。
回答by Jorge Ramos
Answer from @debuggerman is absolutely correct. But you can improve your code if you use [defaults setObject:colour forKey:@"colour”];instead of [defaults setObject:(colour) forKey:@"colour"];
@debuggerman 的回答是绝对正确的。但是如果你使用[defaults setObject:colour forKey:@"colour”];而不是你可以改进你的代码[defaults setObject:(colour) forKey:@"colour"];
Note that I removed the parentheses for object colour.
请注意，我删除了 object 的括号colour。
