Question

我有一个简单的任务，通过GET将一个变量发送到php页面。我似乎没有找到任何作品，而且似乎都比我需要的更多。

似乎我需要代码来设置NSURL字符串，NSURL请求，然后执行。

有人可能会粘贴我一些简单的代码来执行这样的URL：

http://localhost/trendypieces/site/ios/processLatest.php?caption=yosa

谢谢！

这里是最新的一些不起作用的迭代，看起来更接近，因为它实际上会抛出错误警报。不知道那个错误是什么......但是......

//construct an URL for your script, containing the encoded text for parameter value
    NSURL* url = [NSURL URLWithString:
                  [NSString stringWithFormat:
                   @"http://localhost/trendypieces/site/ios/processLatest.php?caption=yosa"]];

    NSData *dataURL =  [NSData dataWithContentsOfURL:url];
    NSString *serverOutput = [[NSString alloc] initWithData:dataURL encoding: NSASCIIStringEncoding];

    if([serverOutput isEqualToString:@"OK"]) {

        alertsuccess = [[UIAlertView alloc] initWithTitle:@"Posted" message:@"Done"
                                                 delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil, nil];

    } else {
        alertsuccess = [[UIAlertView alloc] initWithTitle:@"Error" message:@"Done"
                                                 delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil, nil];

    }
    [alertsuccess show];

Answer 1

有几点：

使用NSURLConnection创建initWithRequest:delegate:时，会自动启动连接。不自己调用start方法（在某些情况下，它可能会干扰初始连接）。这仅适用于将initWithRequest:delegate:startImmediately:与NO一起用于最终参数的情况。
然后你说：

产生无效结果的当前代码（来自IBAction函数）

您的代码不会产生任何＆＃34;有效结果＆＃34;在IBAction方法中。它会调用NSURLConnectionDataDelegate和NSURLConnectionDelegate方法。你有没有实现它们？值得注意的是，请确保您还实施connection:didFailWithError:，它会告诉您是否存在任何连接错误。

如果您需要IBAction方法中的结果，则应使用NSURLConnection方法sendAsynchronousRequest。

转到这个问题的标题，＆＃34;如何发送变量＆＃34;，您应该注意只是将用户输入添加到URL。（这不是您未能得到任何答复的直接问题，但在将变量的内容发送到Web服务器时这很重要。）

值得注意的是，caption=xxx部分，xxx不能包含空格或保留字符，例如+，&等。您需要做的是百分比编码。所以，你应该：

NSString *caption = ... // right now this is @"yosa", but presumably this will eventually be some variable

NSMutableData *data = [[NSMutableData alloc] init];
self.receivedData = data;
// [data release];  // if not ARC, insert this line

//initialize url that is going to be fetched.
NSString *encodedCaption = [self percentEscapeString:caption];
NSURL *url = [NSURL URLWithString:[NSString stringWithFormat:@"http://localhost/trendypieces/site/ios/processLatest.php?caption=%@", encodedCaption]];

//initialize a request from url
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];

//initialize a connection from request
NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:request delegate:self];
self.connection = connection;
// [connection release]; // if not ARC, insert this line

// DO NOT start the connection AGAIN
//[connection start];

percentEscapeString定义为：

- (NSString *)percentEscapeString:(NSString *)string
{
    NSString *result = CFBridgingRelease(CFURLCreateStringByAddingPercentEscapes(kCFAllocatorDefault,
                                                                                 (CFStringRef)string,
                                                                                 (CFStringRef)@" ",
                                                                                 (CFStringRef)@":/?@!$&'()*+,;=",
                                                                                 kCFStringEncodingUTF8));
    return [result stringByReplacingOccurrencesOfString:@" " withString:@"+"];
}

（注意，有一种很有前景的NSString方法，stringByAddingPercentEscapesUsingEncoding，它做了非常相似的事情，但却抵制使用它的诱惑。它处理一些字符（例如空格字符），但不是其他一些（例如+或&个字符。）

最后，您说这是GET请求（这意味着您不会更改服务器上的任何内容）。如果确实是GET请求，请参阅我之前的观点。但是，如果此请求确实在更新数据，那么您应该执行POST请求（caption=yosa在请求正文中，而不是URL）。这有另一个优点，因为URL的长度存在限制（因此在GET请求中在URL中提交参数时，参数可以有多长）。

无论如何，如果你想创建一个POST请求，那就像是：

NSString *caption = ... // right now this is @"yosa", but presumably this will eventually be some variable

NSMutableData *data = [[NSMutableData alloc] init];
self.receivedData = data;
// [data release];  // if not ARC, insert this line

//create body of the request
NSString *encodedCaption = [self percentEscapeString:caption];
NSString *postString = [NSString stringWithFormat:@"caption=%@", encodedCaption];
NSData *postBody = [postString dataUsingEncoding:NSUTF8StringEncoding];

//initialize url that is going to be fetched.
NSURL *url = [NSURL URLWithString:@"http://localhost/trendypieces/site/ios/processLatest.php"];

//initialize a request from url
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
[request setHTTPBody:postBody];
[request setHTTPMethod:@"POST"];
[request setValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"];

//initialize a connection from request
NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:request delegate:self];
self.connection = connection;
// [connection release]; // if not ARC, insert this line

虽然您的初始代码示例使用的是基于委托的NSURLConnection，但您已修改了使用dataWithContentsOfURL的答案。如果您真的不想使用基于委托的NSURLConnection，请改用sendAsynchronousRequest，这样可以提供dataWithContentsOfURL的简单性，但允许您使用GET 1}}或POST请求，以及异步执行。因此，如上所示创建NSMutableURLRequest（根据您是GET还是POST使用适当的方法代码），消除实例化NSMutableData的行和NSURLConnection并将其替换为：

[NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *response, NSData *data, NSError *connectionError) {

    if (!data) {
        NSLog(@"Error = %@", connectionError);

        UIAlertView *alert = [[UIAlertView alloc] initWithTitle:nil message:@"Error" delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil];
        [alert show];

        return;
    }

    NSString *serverOutput = [[NSString alloc] initWithData:data encoding:NSASCIIStringEncoding];

    NSLog(@"Data = %@", serverOutput);

    UIAlertView *alert;

    if ([serverOutput isEqualToString:@"OK"]) {
        alert = [[UIAlertView alloc] initWithTitle:nil message:@"Posted" delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil];
    } else {
        alert = [[UIAlertView alloc] initWithTitle:nil message:@"Not OK" delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil];
    }

    [alert show];
}];

Answer 2

所以主要的问题是尝试从手机而不是模拟器中击中localhost，呃。现在成功运行的代码如下。感谢大家的帮助。

NSURL *url = [NSURL URLWithString:@"http://localhost/trendypieces/site/ios/processLatest.php?caption=mycaption"];

    NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init];
    [request setURL:url];
    [request setHTTPMethod:@"GET"];

    returnData = [[NSMutableData alloc] init];
    NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:request delegate:self startImmediately:YES];

Answer 3

这里适用于带有两个变量的POST，感谢@Rob来自另一个帖子的代码。

NSURL *url = [NSURL URLWithString:@"http://192.168.1.5/trendypieces/site/ios/processLatest.php"];

    NSString *var2 = @"variable2";
    NSString *postString    = [NSString stringWithFormat:@"caption=%@&var2=%@", _captionField.text, var2];
    NSData   *postBody      = [postString dataUsingEncoding:NSUTF8StringEncoding];

    //initialize a request from url
    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
    [request setHTTPBody:postBody];
    [request setHTTPMethod:@"POST"];
    [request setValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"];

    //initialize a connection from request, any way you want to, e.g.
    NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:request delegate:self];

如何将变量从iOS发送到php文件

3 个答案: