autocorrectionType学习

setAutocorrectionType:它默认就是yes，可以禁掉（即设为NO）。
不仅SearchBar、TextField、UITextView，都可用到此Method. 

[searchBar setAutocorrectionType:UITextAutocorrectionTypeNo];
[textField setAutocorrectionType:UITextAutocorrectionTypeNo];
[textView setAutocorrectionType:UITextAutocorrectionTypeNo];

 @property(nonatomic) UITextAutocorrectionType autocorrectionType;         // default is UITextAutocorrectionTypeDefault
typedef NS_ENUM(NSInteger, UITextAutocorrectionType) {
    UITextAutocorrectionTypeDefault,
    UITextAutocorrectionTypeNo,
    UITextAutocorrectionTypeYes,