Limit a double to two decimal places without trailing zeros
I read this and that. I want this exactly:
1.4324 => "1.43"
9.4000 => "9.4" 43.000 => "43"9.4 => "9.40" (wrong)
43.000 => "43.00" (wrong)
In both questions the answers points to NSNumberFormatter
. So it should be easy to achieve, but not for me.
- (void)viewDidLoad {
[super viewDidLoad];
UILabel *myLabel = [[UILabel alloc] initWithFrame:CGRectMake(50, 100, 200, 20)];
NSNumberFormatter *doubleValueWithMaxTwoDecimalPlaces = [[NSNumberFormatter alloc] init];
[doubleValueWithMaxTwoDecimalPlaces setNumberStyle:NSNumberFormatterDecimalStyle];
[doubleValueWithMaxTwoDecimalPlaces setPaddingPosition:NSNumberFormatterPadAfterSuffix];
[doubleValueWithMaxTwoDecimalPlaces setFormatWidth:2];
NSNumber *myValue = [NSNumber numberWithDouble:0.01234];
//NSNumber *myValue = [NSNumber numberWithDouble:0.1];
myLabel.text = [doubleValueWithMaxTwoDecimalPlaces stringFromNumber:myValue];
[self.view addSubview:myLabel];
[myLabel release];
myLabel = nil;
[doubleValueWithMaxTwoDecimalPlaces release];
doubleValueWithMaxTwoDecimalPlaces = nil;
}
I also tried it with
NSString *resultString = [NSString stringWithFormat: @"%.2lf", [myValue doubleValue]];
NSLog(@"%@", resultString);
So how can I format double values with maximum two decimal places? If the last position contains a zero the zero should be left out.
Solution:
NSNumberFormatter *doubleValueWithMaxTwoDecimalPlaces = [[NSNumberFormatter alloc] init];
[doubleValueWithMaxTwoDecimalPlaces setNumberStyle:NSNumberFormatterDecimalStyle];
[double开发者_开发问答ValueWithMaxTwoDecimalPlaces setMaximumFractionDigits:2];
NSNumber *myValue = [NSNumber numberWithDouble:0.01234];
NSLog(@"%@",[doubleValueWithMaxTwoDecimalPlaces stringFromNumber:myValue]];
[doubleValueWithMaxTwoDecimalPlaces release];
doubleValueWithMaxTwoDecimalPlaces = nil;
Try adding the following line, when configuring your formatter:
[doubleValueWithMaxTwoDecimalPlaces setMaximumFractionDigits:2];
NSNumberFormatter *numberFormatter = [[NSNumberFormatter alloc] init];
[numberFormatter setNumberStyle:NSNumberFormatterDecimalStyle];
[numberFormatter setRoundingMode:NSNumberFormatterRoundDown];
[numberFormatter setMinimumFractionDigits:2];
numberFormatter.positiveFormat = @"0.##";
NSNumber *num = @(total_Value);
How about trimming the unwanted characters from the end of the string?:
NSString* CWDoubleToStringWithMax2Decimals(double d) {
NSString* s = [NSString stringWithFormat:@"%.2f", d];
NSCharacterSet* cs = [NSCharacterSet characterSetWithCharacterInString:@"0."];
NSRange r = [s rangeOfCharacterInSet:cs
options:NSBackwardsSearch | NSAnchoredSearch];
if (r.location != NSNotFound) {
s = [s substringToIndex:r.location];
}
return s;
}
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