十六进制颜色转UIColor

很多地方我们都使用16进制颜色，但iPhone使用的是UIColor对象，不直接支持16进制颜色，为此，需要我们手动将16进制颜色转换为UIColor。

- (UIColor *)getColor:(NSString*)hexColor

{

unsigned int red,green,blue;

NSRange range;

range.length = 2;

 

range.location = 0;

[[NSScanner scannerWithString:[hexColor substringWithRange:range]]scanHexInt:&red];

 

range.location = 2;

[[NSScanner scannerWithString:[hexColor substringWithRange:range]]scanHexInt:&green];

 

range.location = 4;

[[NSScanner scannerWithString:[hexColor substringWithRange:range]]scanHexInt:&blue];

 

return [UIColor colorWithRed:(float)(red/255.0f)green:(float)(green / 255.0f) blue:(float)(blue / 255.0f)alpha:1.0f];

}

[self.view setBackgroundColor:[self getColor:@"FF0000"]];

一个面试题：使用内联函数把@“#ff3344”转成UIColor

- (UIColor *) stringTOColor:(NSString *)str
{
    if (!str || [str isEqualToString:@""]) {
        return nil;
    }
    unsigned red,green,blue;
    NSRange range;
    range.length = 2;
    range.location = 1;
    [[NSScanner scannerWithString:[str substringWithRange:range]] scanHexInt:&red];
    range.location = 3;
    [[NSScanner scannerWithString:[str substringWithRange:range]] scanHexInt:&green];
    range.location = 5;
    [[NSScanner scannerWithString:[str substringWithRange:range]] scanHexInt:&blue];
    UIColor *color= [UIColor colorWithRed:red/255.0f green:green/255.0f blue:blue/255.0f alpha:1];
    return color;
}