拨打电话

  程序打电话的实现：

1. 通过UIWebView == 回到程序

UIWebView * view = [[UIWebView alloc] init];
    NSString * str = @"tel:1388888888";
    NSURL * url = [NSURL URLWithString:str];
    NSURLRequest * request = [NSURLRequest requestWithURL:url];
    [view loadRequest:request];

2。系统的打电话 - 回到系统界面

NSString * str1 = @"13199999999";
    [[UIApplication sharedApplication] openURL:[NSURL URLWithString:str1]];

3.系统，但是通话结束，回到程序

NSString * str2 = [NSString stringWithFormat:@"telprompt://%@",@"13166666666"];
    [[UIApplication sharedApplication] openURL:[NSURL URLWithString:str2]];