android应用程序中的Android-Studio-HTTP连接处理

Question

我有麻烦了。我无法连接到MySQL服务器。我学习了这个教程simplifiedcoding.net/android-php-mysql-login-tutorial-android-login-app-3/,我想做一个简单的PHP MySQL登录。但有些东西，如'NameValuePair'、'BasicNameValuePair'、'HttpClient'、'HttpPost'、'HttpResponse'、'HttpEntity'、'UrlenCodedFormEntity'等，则不推荐使用。我想问一下，有人能把这个编码正确吗？还是帮我？

下面是无法正常工作的代码：（谢谢您的帮助）

@Override
            protected String doInBackground(String... params) {
                String uname = params[0];
                String pass = params[1];

                InputStream is = null;
                List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
                nameValuePairs.add(new BasicNameValuePair("username", uname));
                nameValuePairs.add(new BasicNameValuePair("password", pass));
                String result = null;

                try{
                    HttpClient httpClient = new DefaultHttpClient();
                    HttpPost httpPost = new HttpPost("site.com/login.php");
                    httpPost.setEntity(new UrlEncodedFormEntity(nameValuePairs));

                    HttpResponse response = httpClient.execute(httpPost);

                    HttpEntity entity = response.getEntity();

                    is = entity.getContent();

                    BufferedReader reader = new BufferedReader(new InputStreamReader(is, "UTF-8"), 8);
                    StringBuilder sb = new StringBuilder();

                    String line = null;
                    while ((line = reader.readLine()) != null)
                    {
                        sb.append(line + "\n");
                    }
                    result = sb.toString();
                } catch (ClientProtocolException e) {
                    e.printStackTrace();
                } catch (UnsupportedEncodingException e) {
                    e.printStackTrace();
                } catch (IOException e) {
                    e.printStackTrace();
                }
                return result;
            }

Answer 1

实际上你发布的链接是从我的网站。当我写这篇教程的时候，这些课程并没有被弃用。如果你会检查我的网站，那么我已经张贴了一个更新的教程。

要向web服务器发送http post请求，可以使用以下代码。

public class RequestHandler {
public String sendPostRequest(String requestURL,
                              HashMap<String, String> postDataParams) {
    URL url;

    StringBuilder sb = new StringBuilder();
    try {
        url = new URL(requestURL);

        HttpURLConnection conn = (HttpURLConnection) url.openConnection();

        conn.setReadTimeout(15000);
        conn.setConnectTimeout(15000);
        conn.setRequestMethod("POST");
        conn.setDoInput(true);
        conn.setDoOutput(true);

        OutputStream os = conn.getOutputStream();

        BufferedWriter writer = new BufferedWriter(
                new OutputStreamWriter(os, "UTF-8"));
        writer.write(getPostDataString(postDataParams));

        writer.flush();
        writer.close();
        os.close();
        int responseCode = conn.getResponseCode();

        if (responseCode == HttpsURLConnection.HTTP_OK) {

            BufferedReader br = new BufferedReader(new InputStreamReader(conn.getInputStream()));
            sb = new StringBuilder();
            String response;
            while ((response = br.readLine()) != null){
                sb.append(response);
            }
        }

    } catch (Exception e) {
        e.printStackTrace();
    }
    return sb.toString();
}

private String getPostDataString(HashMap<String, String> params) throws UnsupportedEncodingException {
    StringBuilder result = new StringBuilder();
    boolean first = true;
    for (Map.Entry<String, String> entry : params.entrySet()) {
        if (first)
            first = false;
        else
            result.append("&");

        result.append(URLEncoder.encode(entry.getKey(), "UTF-8"));
        result.append("=");
        result.append(URLEncoder.encode(entry.getValue(), "UTF-8"));
    }

    return result.toString();
}
}

现在，您需要做的只是在主活动中创建一个AsyncTask和doInBackGround方法

更多详情请访问Android PHP mysql-crud操作