我像这样向我的服务器发送一个发布请求。:
-(Produkt*)fetchProductByID:(int)idNumber
{
NSString* command = @"fetchProduct";
NSString* number = [NSString stringWithFormat:@"%d",idNumber];
NSMutableDictionary* params =[NSMutableDictionary dictionaryWithObjectsAndKeys:
                              command, @"command",
                              number, @"id",
                              nil];
[self commandWithParams:params onCompletion:^(NSDictionary *json)
 {
     //result returned
     NSDictionary* res = [[json objectForKey:@"result"] objectAtIndex:0];
     NSMutableArray* dics = [[NSMutableArray alloc]init];
     if ([json objectForKey:@"error"]==NULL && [res count]>0)
     {
         //success
         for(int i=0;i<[[json objectForKey:@"result"]count];i++)
         {
             res = [[json objectForKey:@"result"] objectAtIndex:i];
             [dics addObject:res];
             NSLog(@"SPECIAL FETCHED PRODUKT:%@",res);
         }
     }
     else
     {
         //error
         NSLog(@"error:%@",[json objectForKey:@"error"]);
         res = [[json objectForKey:@"result"] objectAtIndex:0];
         NSLog(@"SPECIAL FETCHED PRODUKT:%@",res);
     }
 }];
return NULL;
}
但我总是收到这个错误:错误:无法完成操作。(Cocoa 错误 3840。) index.php 代码如下所示:
<?
 require("lib.php");
require("QMServerAPI.php");
header("Content-Type: application/json");
switch ($_POST['command']) 
{
  case "fetchAllProduct": //Different question
  fetchAllProduct(); 
  break;
  case "fetchProduct":
  fetchProduct($_POST['id']);
  break;
  case "insertProduct":
  insertProduct($_POST['name'], $_POST['artikelNr'],
   $_POST['anleitung'], $_POST['image'], $_POST['editDate'],
   $_POST['id']); 
  break;
  case "updateProduct":
  updateProduc($_POST['name'], $_POST['artikelNr'],
  $_POST['anleitung'], $_POST['image'], $_POST['editDate'],
  $_POST['id']);
  break;
 }
 ?>
这里我执行命令:
function errorJson($msg)
{
  header('Content-type: application/json');
  print json_encode(array("error"=>$msg));
  exit();
}
function fetchAllProduct()
{
     //fetch all Products
     $result = query("SELECT * FROM Produkte");
     print json_encode($result);
}
function fetchProduct($id)
{
      //fetch specific product 
      $result  = query("SELECT * FROM Produkte WHERE id = '122'");
      print jeson_encode($result);
 }
  function insertProduct($name, $artikelNr, $anleitung, $image, 
              $editDate, $id)
 {
  }
    function updateProduct($name, $artikelNr, $anleitung, $image, 
              $editDate, $id)
   {
   //update old product
   }
?>
这是查询功能的代码:
<?
     //setup db connection
   $link = mysqli_connect("localhost","root","");
   mysqli_select_db($link, "QM");
   //executes a given sql query with the params and returns an array as result
    function query() {
   global $link;
  $debug = false;
   //get the sql query
  $args = func_get_args();
  $sql = array_shift($args);
     //secure the input
    for ($i=0;$i<count($args);$i++) {
      $args[$i] = urldecode($args[$i]);
     $args[$i] = mysqli_real_escape_string($link, $args[$i]);
   }
   //build the final query
  $sql = vsprintf($sql, $args);
  if ($debug) print $sql;
   //execute and fetch the results
      $result = mysqli_query($link, $sql);
     if (mysqli_errno($link)==0 && $result) {
  $rows = array();
  if ($result!==true)
  while ($d = mysqli_fetch_assoc($result)) {
     array_push($rows,$d);
  }
  //return json
  return array('result'=>$rows);
 } else {
  //error
  return array('error'=> $mysqli->error);
 }
}
我不知道出了什么问题,因为当我选择所有产品时它工作正常。当我使用 WHERE 时,错误才出现。
谢谢你的帮助。