A[[UIApplicationsharedApplication]openURL:[NSURLURLWithString:@"tel://10086"]];
B[[UIApplicationsharedApplication]openURL:[NSURLURLWithString:@"tel:10086"]];
C[[UIApplicationsharedApplication]openURL:[NSURLURLWithString:@"tel 10086"]];
D[[UIApplicationsharedApplication]openURL:[NSURLURLWithString:@"tel:\\10086"]];