有关Assigned的说法哪个是正确的?()
A: 其他三项都不对
B: Assigned的作用是判断一个对象是否为Nil,如果是Nil,返回True,如果不是Nil,返回False
C: Assigned的参数可以是对象或者方法,或者是一个指针
D: Assigned的作用是判断Assign过程是否已经完成
A: 其他三项都不对
B: Assigned的作用是判断一个对象是否为Nil,如果是Nil,返回True,如果不是Nil,返回False
C: Assigned的参数可以是对象或者方法,或者是一个指针
D: Assigned的作用是判断Assign过程是否已经完成
举一反三
- x in s的作用是判断x是否是s的子串,如果是返回True,否则返回False。
- 下列使用方法中正确的是()。 A: NSURL*url=nil; B: Classclass=Nil; C: idfoo=nil; D: idfoo=NIL;
- 根据每个句子所表达的意思判断下列句子使用修饰语是否正确The teacher assigned the homework quickly, which frustrated the students.(You mean that the teacher assigned the homework quickly)
- It is not advisable that Tim ______to the job, because he has no relative experience. A: A) is assigned B: C) be assigned C: B) will be assigned D: D) has been assigned
- I don't think it is advisable that Ted __________ to the job since he has little experience. A: assigned B: be assigned C: was assigned D: will be assigned