ios开发中浮点型精度丢失处理

我们在开发中容易遇到浮点型精度丢失

• 比如2.36会变成2.359999999

• 如何把浮点型正确显示到界面呢？

  NSDecimalNumber * number = [NSDecimalNumber decimalNumberWithString:[NSString stringWithFormat:@"%lf",2.36]];
  NSDecimal resultStruct;
  NSDecimal str = number.decimalValue;
  NSDecimalRound(&resultStruct, &str, 3, NSRoundPlain); // 四舍五入保留3为小数，末尾没有0
  NSDecimalNumber * resultNumber = [NSDecimalNumber decimalNumberWithDecimal:resultStruct];
  NSString * str  = [resultNumber stringValue];