php - Volley POST 字符串请求意外错误 500

Question

我在我的项目中使用 Volley 库并获得 Unexpected response code 500作为回应。

我已经彻底搜索了 stackoverflow，但仍然找不到有效的解决方案。

以下是我发出 GET 字符串请求的代码

        val API = "http://squadtechsolution.com/android/v1/allcompany.php"
        val requestQueue = Volley.newRequestQueue(mActivity)
        val stringRequest = StringRequest(
            Request.Method.GET,
            API,
            Response.Listener { response ->
                Log.i("dxdiag", response)
                mView.onFetchHttpDataResult(true)
                Toast.makeText(context, response, Toast.LENGTH_LONG).show()
            },
            Response.ErrorListener { error ->
                Toast.makeText(context, error.toString(), Toast.LENGTH_LONG).show()
                Log.i("dxdiag", error.printStackTrace().toString())
                mView.onFetchHttpDataResult(false)
            })
        requestQueue.add(stringRequest)

以下是堆栈跟踪

2019-09-03 17:15:53.237 3308-3892/com.squadtechs.markhor.foodapp 
E/Volley: [194] BasicNetwork.performRequest: Unexpected response code 
500 for 
http://squadtechsolution.com/android/v1/allcompany.php
2019-09-03 17:15:53.243 3308-3351/com.squadtechs.markhor.foodapp 
D/EGL_emulation: eglMakeCurrent: 0xa7d84180: ver 2 0 (tinfo 
0xa7d832b0)
2019-09-03 17:15:53.256 3308-3308/com.squadtechs.markhor.foodapp 
W/System.err: com.android.volley.ServerError
2019-09-03 17:15:53.257 3308-3308/com.squadtechs.markhor.foodapp 
W/System.err:     at com.android.volley.toolbox.BasicNetwork.performRequest(BasicNetwork.java:205)2019-09-03 17:15:53.257 3308-3308/com.squadtechs.markhor.foodapp W/System.err:     at com.android.volley.NetworkDispatcher.processRequest(NetworkDispatcher.java:131)2019-09-03 17:15:53.257 3308-3308/com.squadtechs.markhor.foodapp W/System.err:     at com.android.volley.NetworkDispatcher.processRequest(NetworkDispatcher.java:111)2019-09-03 17:15:53.257 3308-3308/com.squadtechs.markhor.foodapp W/System.err:     at com.android.volley.NetworkDispatcher.run(NetworkDispatcher.java:90)

以下是我在服务器端编写的 PHP 代码:

<?php
    require 'db.php';

    $sql = "SELECT * FROM `company_profile`";
    $result = $con->query($sql);

    if ($result->num_rows > 0) {
    // output data of each row
    while($row = $result->fetch_assoc()) {

        $id=$row['id']; 

        $company_name=$row['company_name'];
        $cuisine=$row['cuisine'];
        $conpany_phone=$row['conpany_phone'];
        $company_description=$row['company_description']; 
        $company_logo=$row['company_logo'];
        $company_type=$row['company_type'];
        $delivery_type=$row['delivery_type'];
        $delivery_range=$row['delivery_range']; 
        $delivery_fee=$row['delivery_fee'];
        $delivery_pickupinfo=$row['delivery_pickupinfo'];
        $address=$row['address'];

        $companyData[] = array('id'=> $id,'company_name'=> 
        $company_name,'cuisine'=> $cuisine,'conpany_phone'=> 
        $conpany_phone,'company_description'=> 
        $company_description,'company_logo'=> $company_logo,'company_type'=> 
        $company_type,'delivery_type'=> $delivery_type,'delivery_range'=> 
        $delivery_range,'delivery_fee'=> 
        $delivery_fee,'delivery_pickupinfo'=> $delivery_pickupinfo,'address'=> $address);   
    }
    echo $jsonformat=json_encode($companyData);
    } else {
        echo "0 results";
    }
    $conn->close();
?>

Answer 1

我稍微修改了代码并在 postman 中检查了它，它工作正常。

我将 JSON 编码语句从 if 语句中移出。

// output data of each row
while($row = $result->fetch_assoc()) {

    $id=$row['id']; 

    $company_name=$row['company_name'];
    $cuisine=$row['cuisine'];
    $conpany_phone=$row['conpany_phone'];
    $company_description=$row['company_description']; 
    $company_logo=$row['company_logo'];
    $company_type=$row['company_type'];
    $delivery_type=$row['delivery_type'];
    $delivery_range=$row['delivery_range']; 
    $delivery_fee=$row['delivery_fee'];
    $delivery_pickupinfo=$row['delivery_pickupinfo'];
    $address=$row['address'];

    $companyData[] = array('id'=> $id,'company_name'=> 
    $company_name,'cuisine'=> $cuisine,'conpany_phone'=> 
    $conpany_phone,'company_description'=> 
    $company_description,'company_logo'=> $company_logo,'company_type'=> 
    $company_type,'delivery_type'=> $delivery_type,'delivery_range'=> 
    $delivery_range,'delivery_fee'=> 
    $delivery_fee,'delivery_pickupinfo'=> $delivery_pickupinfo,'address'=> $address);   
}
echo $jsonformat=json_encode($companyData);

$conn->close();