OC NSString Summary

1. Initialization

2. Common methods

Stitching strings

Determine if the same string

[Answer Isequaltostring:self.currentmodel.answer]//answer==self.currentmodel.answer Difference

3. Comparison of methods

Nssttring stringbyappendingstring//nsstring Immutable, each append generates a new NSString

Nsmulbtblestring AppendString//nsmulbtblestring operation itself

1 __block NSString * answer = [nsstring new]; 2[Self.answerView.subviews enumerateobjectsusingblock:^ (__kindof UIView * _nonnull obj, Nsuinteger idx, BOOL *_nonnull stop) {3UIButton * button = (uibutton*) obj;4         answer = [Answer stringByAppendingString:button.currentTitle]; 5     }];6 7 8 9 __block nsmutablestring * answer = [nsmutablestring string]; Ten[Self.answerView.subviews enumerateobjectsusingblock:^ (__kindof UIView * _nonnull obj, Nsuinteger idx, BOOL *_nonnull stop) { OneUIButton * button = (uibutton*) obj; A [Answer AppendString:button.currentTitle]; -}];

OC NSString Summary