用途：根據(jù)報(bào)錯(cuò)調(diào)用的方法名來快速估計(jì)出錯(cuò)的位置桨武，可能某個(gè)對象被當(dāng)作另一個(gè)對象使用了
報(bào)錯(cuò)例子：
-[UIView setSelected:]: unrecognized selector sent to instance 0x7ff3f35b1070
可能是誤將uiview當(dāng)UIButton使用揭保，調(diào)用了setSelected
注：Person為NSObject
-[Person length]: unrecognized selector sent to instance 0x7ff3f35b1070
錯(cuò)誤將Person當(dāng)做NSString來使用,比如
id obj = [[Person alloc] init];
NSString *string = obj;
string.length;
-[Person count]: unrecognized selector sent to instance 0x7ff3f35b1070
誤將Person當(dāng)數(shù)組使用
id obj = [[Person alloc] init];
NSArray *array = obj;
array.count;
-[Person setObject:forKeyedSubscript:]: unrecognized selector sent to instance 0x7ff3f35b1070
錯(cuò)誤將Person當(dāng)做NSMutableDictionary來使用
規(guī)律: 方法名里面包含了Subscript的方法,一般都是集合的方法(比如字典\數(shù)組)
