Create a CAGradientLayer from a CSS string in the "background-image(linear-gradient(top, #cb60b3 0%,#c146a1 50%,#a80077 51%,#db36a4 100%));" format

gradient.m

+(CAGradientLayer *)layerFromArray:(NSArray *)gradientsArray
{
    //create gradient from gradient
    NSMutableArray *arrayOfColors = [NSMutableArray arrayWithCapacity:10];
    NSMutableArray *arrayOfPositions = [NSMutableArray arrayWithCapacity:10];
    
    for (NSString *string in gradientsArray)
    {
        NSArray *arr = [string componentsSeparatedByString:@","];
        
        //color as hex
        NSString *hex = [arr objectAtIndex:0];
        
        //float value
        float colorPosition = [[arr objectAtIndex:1] floatValue];
        
        [arrayOfColors addObject:(id)[UIColor colorWithHexString:[hex uppercaseString]].CGColor];
        [arrayOfPositions addObject:[NSNumber numberWithFloat:colorPosition]];
    }
    
    CAGradientLayer *headerLayer = [CAGradientLayer layer];
    headerLayer.colors = [NSArray arrayWithArray:arrayOfColors];
    headerLayer.locations = [NSArray arrayWithArray:arrayOfPositions];
    
    return headerLayer;
}
+(CAGradientLayer *)css3Style:(NSString *)string
{
    //will find any pattern of #cb60b3 0%,#cb60b3 0%
    //CSS > @include background-image(linear-gradient(top, #cb60b3 0%,#c146a1 50%,#a80077 51%,#db36a4 100%));;
    
    CAGradientLayer *gradient = nil;
    
    NSString *regexStr = @"#[a-zA-Z0-9]{3,6} [0-9]{1,3}%";
    NSError *error = nil;
    
    NSRegularExpression *testRegex = [NSRegularExpression regularExpressionWithPattern:regexStr options:0 error:&error];
    
    if( testRegex == nil ) NSLog( @"Error making regex: %@", error );
    
    NSInteger matches = [testRegex numberOfMatchesInString:string options:0 range:NSMakeRange(0, [string length])];
    
    __block NSMutableArray *arrayOfGradients = [NSMutableArray arrayWithCapacity:10];
    
    if (matches>0) {
        [testRegex enumerateMatchesInString:string options:0 range:NSMakeRange(0, [string length]) usingBlock:^(NSTextCheckingResult *result, NSMatchingFlags flags, BOOL *stop) {
            
            //separate values into array
            NSArray *values = [[string substringWithRange:result.range] componentsSeparatedByString:@" "];
            
            //convert percent to a float value
            float percentValue = [[[values objectAtIndex:1] stringByReplacingOccurrencesOfString:@"%" withString:@""] floatValue];
            
            //find the value from 100
            float floatValue = (float)percentValue/100.0f;
            
            //create new string by appending , in between 
            NSString *newString = [[NSArray arrayWithObjects:[values objectAtIndex:0],[NSString stringWithFormat:@"%f",floatValue], nil] componentsJoinedByString:@","];
            
            [arrayOfGradients addObject:newString];
            
        }];
        
        //return gradient
        gradient = [self layerFromArray:arrayOfGradients];
    }
    
    return gradient;
}