How get the total sum of currency from a NSMutable

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ios - How get the total sum of float from a NSMutableArray 3 answers

I want to sum of currency from NSMutableArray. Ex: I have an arrayA (1,234.56 , 2,345.67) and after sum items in array, I want result show: 3,580.23 to put it on the Label. Is there the way to implement this?

Thanks

回答1:

If the values are stored as NSNumber objects, you can use the collection operators. For example:

NSArray *array = @[@1234.56, @2345.67];
NSNumber *sum = [array valueForKeyPath:@"@sum.self"];

If you want to format that sum nicely using NSNumberFormatter:

NSNumberFormatter *formatter = [[NSNumberFormatter alloc] init];
formatter.numberStyle = NSNumberFormatterDecimalStyle;
NSString *result = [formatter stringFromNumber:sum];

NSLog(@"result = %@", result);

If your values are really represented by strings, @"1,234.56", @"2,345.67", etc., then you might want to manually iterate through the array, converting them to numeric values using the NSNumberFormatter, adding them up as you go along:

NSNumberFormatter *formatter = [[NSNumberFormatter alloc] init];
formatter.numberStyle = NSNumberFormatterDecimalStyle;

NSArray *array = @[@"1,234.56", @"2,345.67"];

double sum = 0.0;

for (NSString *string in array) {
    sum += [[formatter numberFromString:string] doubleValue];
}

NSString *result = [formatter stringFromNumber:@(sum)];

NSLog(@"result = %@", result);

回答2:

The simplest way is this:

NSMutableArray *array = [NSMutableArray arrayWithArray:@[@(1234.56), @(2345.67)]];
double sum = [[array valueForKeyPath: @"@sum.self"] doubleValue];