iOS获取UIColor对象的RGB值

- (NSDictionary *)getRGBDictionaryByColor:(UIColor *)originColor

{

CGFloat r=0,g=0,b=0,a=0;

if ([self
respondsToSelector:@selector(getRed:green:blue:alpha:)]) {

[originColor
getRed:&r green:&g
blue:&b alpha:&a];

}

else {

const CGFloat *components =
CGColorGetComponents(originColor.CGColor);

r = components[0];

g = components[1];

b = components[2];

a = components[3];

}

return @{@"R":@(r),

@"G":@(g),

@"B":@(b),

@"A":@(a)};

}