I got a string: "1+2+3232+4" which I would like to turn the answer: 3239.
How do I do this in Objective-C?
3 Answers
For simple expressions, you can use NSExpression:
NSExpression *e = [NSExpression expressionWithFormat:@"1+2+3232+4"];
NSNumber *result = [e expressionValueWithObject:nil context:nil];
NSLog(@"%@", result);
For more complicated expression, you should use a proper math expression parser, e.g. https://github.com/davedelong/DDMathParser.
Remark: One potential problem with this approach can be that integers are not
automatically converted to floating point numbers. For example,
"4/3" evaluates to 1, not to 1.3333333.
Comments
NSString *string = @"1+2+3232+4";
NSArray *array = [string componentsSeparatedByString:@"+"];
NSInteger result = 0;
for (NSString *value in array)
result += [value integerValue];
NSLog(@"%i", result);
1 Comment
Martin R
Just a remark: You could also use Key-Value Coding to compute the sum:
NSNumber *sum = [array valueForKeyPath:@"@sum.self"];This is use for float/int Value also
NSString *myStringNumber = @"5+1+2+3.5+4/5+3.5*86";
NSArray *convertNumber = [myStringNumber componentsSeparatedByString:@"+"];
float sumValue = 0;
for (NSString *number in convertNumber) {
sumValue += [number floatValue];
}
NSLog(@"Result is : %f", sumValue);
componentsSeparatedByStringwhich return aNSArray, do the addition, and then convert into anint.