【单选题】二层办公室的楼面面层采用( )。 (2.5)

【单选题】Now a paper in Science argues that organic chemicals in the rock come mostly from ______ on earth rather than bacteria on Mars.

【判断题】在swift里面String和NSString都是继承NSObject类型的。（ ）

【单选题】二层办公室的楼面面层采用( )。 图纸.zip

【简答题】阅读下列代码 - (NSString *)description { return [NSString stringWithFormat:@"%@", self];}下列关于程序执行结果的描述中，正确的是（）。A. 无输出结果 B. 程序陷入死循环 C. 循环引用 D. .无错误

【单选题】Now a paper argues that organic chemicals in the rock come mostly from ____ on earth rather than bacteria on Mars.

【单选题】阅读以下一段代码: NSString *home = NSHomeDirectory(); NSString *documents = [home stringByAppendingPathComponent:@"Documents"]; 分析代码可知,它的目的在于获取()目录。

【单选题】Now a paper in Science argues that organic chemicals in the rock come mostly from ________ on earth rather than bacteria on Mars.

【简答题】阅读以下一段代码： NSString *home = NSHomeDirectory(); NSString *documents = [home stringByAppendingPathComponent:@"Documents"]; 分析代码可知，它的目的在于获取（）目录。A. tmp B. Documents C. Library/Caches D. Library/Preferen...

【简答题】String 与 NSString 的关系与区别