mysql/androidstudio，table 上的列只接受 int，而不是 varchar

Question

我试图在 table 中插入行，但是“部门”列只接受整数。我正在使用这个 Tutorial 作为我的指南。

如果我将第 4 列（部门）的类型更改为 int 并在其上插入 int，一切正常。但我需要字符串。我已经将上述列的类型更改为 VARCHAR，但在 table 上始终显示“0”，即使我插入一个字符串也是如此。

我的Table

这是我的 table 结构

API.php

<?php 
require_once '../includes/DbOperation.php';
function isTheseParametersAvailable($params){
    $available = true; 
    $missingparams = ""; 
    
    foreach($params as $param){
        if(!isset($_POST[$param]) || strlen($_POST[$param])<=0){
            $available = false; 
            $missingparams = $missingparams . ", " . $param; 
        }
    }
    if(!$available){
        $response = array(); 
        $response['error'] = true; 
        $response['message'] = 'Parameters ' . substr($missingparams, 1, strlen($missingparams)) . ' missing';
        echo json_encode($response);
                die();
    }
}

$response = array();

if(isset($_GET['apicall'])){
    
    switch($_GET['apicall']){
        
        //the CREATE operation
        //if the api call value is 'createhero'
        //we will create a record in the database
        case 'createemployee':
            //first check the parameters required for this request are available or not 
            isTheseParametersAvailable(array('firstname','lastname','department','image'));
            
            //creating a new dboperation object
            $db = new DbOperation();
            
            //creating a new record in the database
            $result = $db->createEmployee(
                $_POST['firstname'],
                $_POST['lastname'],
                $_POST['department'],
                $_POST['image']
            
    
            );
            

            //if the record is created adding success to response
            if($result){
                //record is created means there is no error
                $response['error'] = false; 

                //in message we have a success message
                $response['message'] = 'Employee addedd successfully';

                //and we are getting all the heroes from the database in the response
            //  $response['employees'] = $db->getHeroes();
            }else{

                //if record is not added that means there is an error 
                $response['error'] = true; 

                //and we have the error message
                $response['message'] = 'Some error occurred please try again';
            }
            
        break;

Dboperation.php

class DbOperation{
private $con;
function __construct()
{
    //Getting the DbConnect.php file
    require_once dirname(__FILE__) . '/DbConnect.php';

    //Creating a DbConnect object to connect to the database
    $db = new DbConnect();

    //Initializing our connection link of this class
    //by calling the method connect of DbConnect class
    $this->con = $db->connect();
}

/*
* The create operation
* When this method is called a new record is created in the database
*/
function createEmployee($firstname, $lastname, $department, $image){
    $stmt = $this->con->prepare("INSERT INTO tbl_users (firstname, lastname, department, image) VALUES (?, ?, ?, ?)");
    $stmt->bind_param("ssis", $firstname, $lastname, $department, $image);
    if($stmt->execute())
        return true; 
    return false; 
}

Android代码

private void createEmployee1() {
    String firstname = EtFirstname.getText().toString().trim();
    String lastname = EtLastname.getText().toString().trim();
    String department = EtDepartment.getText().toString().trim();
    String image = EtImage.getText().toString().trim();
    
    HashMap<String,String> params = new HashMap<>();
    params.put("firstname", firstname);
    params.put("lastname", lastname);
    params.put("department", department);
    params.put("image", image);

   PerformNetworkRequest request = new PerformNetworkRequest(Api.URL_CREATE_EMPLOYEE, params, CODE_POST_REQUEST);
   request.execute();
}


private class PerformNetworkRequest extends AsyncTask<Void, Void , String> {
    String url;
    HashMap<String, String> params;
    int requestCode;

    PerformNetworkRequest(String url, HashMap<String, String> params, int requestCode) {
        this.url = url;
        this.params = params;
        this.requestCode = requestCode;
    }

    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        progressBar.setVisibility(View.VISIBLE);

    }

    @Override
    protected void onPostExecute(String s) {
        super.onPostExecute(s);
        progressBar.setVisibility(View.GONE);
        try {
            JSONObject object = new JSONObject(s);
            if (!object.getBoolean("error")) {
                Toast.makeText(getApplicationContext(), object.getString("message"), Toast.LENGTH_SHORT).show();
 
            }
        } catch (JSONException e) {
            e.printStackTrace();
        }
    }

    @Override
    protected String doInBackground(Void... voids) {
        RequestHandler requestHandler = new RequestHandler();

        if (requestCode == CODE_POST_REQUEST)
            return requestHandler.sendPostRequest(url, params);


        if (requestCode == CODE_GET_REQUEST)
            return requestHandler.sendGetRequest(url);

        return null;
    }

}

Api.java

public class Api {
  private static final String ROOT_URL = "http://XXX.XXX.X.XX:8080/DTR/v1/Api.php?apicall=";



    public static final String URL_CREATE_EMPLOYEE = ROOT_URL + "createemployee";
    public static final String URL_READ_EMPLOYEE = ROOT_URL + "getemployees";
    public static final String URL_UPDATE_EMPLOYEE = ROOT_URL + "updateemployee";
    public static final String URL_DELETE_EMPLOYEE = ROOT_URL + "deleteemployee&id=";

}

Answer 1

$stmt->bind_param("ssis", $firstname, $lastname, $department, $image);

对于 ssis 中的 i，您在此处指定的第三个插入值应该是一个整数，因此它被视为整数，包括将无效值转换为 0。

mysql/androidstudio，table 上的列只接受 int，而不是 varchar

mysql/androidstudio, column on table only accepts int, instead of varchar

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