小编Pho*_*698的帖子

我试图执行一个查询并通过结果迭代.这些echo "<h1>" . $row["SummonerId"]. "</h1>";作品将在页面上打印出来.但不知何故,这个错误发生在打印结果后:

致命错误:在字符串上调用成员函数fetch_assoc()

我看到很多类似的错误.但那些是on a non-object和不是on string.这个错误是什么？

这是我的代码:

$servername = "localhost:3307";
$username = "root";
$password = "";
$dbname = "st-datacollector";

$conn = new mysqli($servername, $username, $password, $dbname);

$sql = "SELECT * FROM summoner";
$result = $conn->query($sql);

if ($result->num_rows > 0) {
    while($row = $result->fetch_assoc()) {
        echo "<h1>" . $row["SummonerId"]. "</h1>";  
        $summonerId = $row["SummonerId"];
        $url = "https://euw.api.pvp.net/api/lol/euw/v1.3/game/by-summoner/" . $summonerId . "/recent?api_key=" . $api_key;

        $result = file_get_contents($url);
        $resultJSON = json_decode($result);


        foreach($resultJSON_decoded->games as $game){ …

我想用Graphics2D在Java中使用Color 2 Ovals.Oval1(point)绿色和椭圆形2(point2)蓝色.问题是Oval2变成绿色而Oval1变成黑色.有人知道问题是什么吗？

左(oval1)右(oval2)

这是SSCCE:

GameView.java

import javax.swing.JFrame;
import stackoverflow.GameView;

public class GameView extends JFrame{
    /**
     * 
     */
    private static final long serialVersionUID = 1L;

    private Game game = new Game();

    public GameView(){
        JFrame gameFrame = new JFrame("Game");
        gameFrame.setSize(500, 300);
        gameFrame.setVisible(true);
        gameFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        gameFrame.add(game);        
        game.runGame();
    }

    public static void main(String[] args) throws InterruptedException {
        new GameView();     
    }
}

Game.java

import java.awt.Color;
import java.awt.Graphics;
import javax.swing.JPanel;
import stackoverflow.Point;

public class Game extends JPanel{
    /**
     * 
     */
    private static …