NSNumber *number =@64.4;
double d = [number doubleValue];
// 直接轉(zhuǎn)換 NSNumber->NSString
NSString *text1 = [number stringValue];
// NSNumber-> Double ->NSString ->NSDecimalNumber ->NSString
NSString *dStr = [NSString stringWithFormat:@"%f", d];
NSDecimalNumber *dn =[NSDecimalNumber decimalNumberWithString:dStr];
NSString *text2 = [dn stringValue];
// NSNumber-> Double ->NSString
NSString *text3 = [NSString stringWithFormat:@"%f", d];
NSLog(@"text1 ==== %@ text2 ===== %@ text3 ===== %@",text1,text2,text3);
輸出
2020-12-14 19:36:57.614561+0800 DelegateDemo[13970:359440]
text1 ==== 64.40000000000001 text2 ===== 64.4 text3 ===== 64.400000
