ios开发之16进制颜色(html颜色值)字符串转为UIColor

互联网 App 中经常会用到 html 颜色值转换 UIColor，比如：#FF9900、0XFF9900 等颜色字符串，以下方法可以将这些字符串转换为 UIColor 对象。

+ (UIColor *) colorWithHexString: (NSString *)color

{

NSString *cString = [[color stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]] uppercaseString];

// String should be 6 or 8 characters

if ([cString length] < 6) {

return [UIColor clearColor];

}

// strip 0X if it appears

if ([cString hasPrefix:@"0X"])

cString = [cString substringFromIndex:2];

if ([cString hasPrefix:@"#"])

cString = [cString substringFromIndex:1];

if ([cString length] != 6)

return [UIColor clearColor];

// Separate into r, g, b substrings

NSRange range;

range.location = 0;

range.length = 2;

//r

NSString *rString = [cString substringWithRange:range];

//g

range.location = 2;

NSString *gString = [cString substringWithRange:range];

//b

range.location = 4;

NSString *bString = [cString substringWithRange:range];

// Scan values

unsigned int r, g, b;

[[NSScanner scannerWithString:rString] scanHexInt:&r];

[[NSScanner scannerWithString:gString] scanHexInt:&g];

[[NSScanner scannerWithString:bString] scanHexInt:&b];

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

}