if
(YES
== [[NSUserDefaults
standardUserDefaults]boolForKey:@"isNight"])
{
[self.web
stringByEvaluatingJavaScriptFromString:@"document.getElementsByTagName('body')[0].style.background='#BABABA'"];
}
else {
[self.web
stringByEvaluatingJavaScriptFromString:@"document.getElementsByTagName('body')[0].style.background='#FFFFFF'"];
}
注 : 放在 - (void)webViewDidFinishLoad:(UIWebView *)webView 方法里