Php 在MySql Android中从多个tahn one表获取数据

我想在android应用程序中显示来自mysql的多个表，我使用这段php代码显示了一个表

PHP

---

这有点猜测，但我认为这就是你想要的：

//...
$table1 = Array();
$table2 = Array();
$sql = "SELECT * FROM table1 ORDER BY id DESC";
$result = $conn->query($sql);

if ($result->num_rows >0) {
  // get the result for first table and save it into an array ($table1)
  while($row = $result->fetch_assoc()) {
     $table1[] = $row;
  }
} else {
  echo "0 results";
}

// just do the same for any other table
$sql = "SELECT * FROM table2 ORDER BY id DESC";
$result = $conn->query($sql);

if ($result->num_rows >0) {
  while($row = $result->fetch_assoc()) {
     $table2[] = $row;
  }
} else {
  echo "0 results";
}
// here you put together what you wanna return:
$return = Array('table1' => $table1, 
                'table2' => $table2);
// encode it
$json = json_encode($return,JSON_UNESCAPED_UNICODE);

echo $json;

但是：
最好将其封装到函数中：

//...
function getTable($conn, $tableName) {
    $sql = "SELECT * FROM $tableName ORDER BY id DESC";
    $result = $conn->query($sql);
    $tableResult = Array();

    if ($result->num_rows >0) {
       while($row = $result->fetch_assoc()) {
          $tableResult[] = $row;
       }
    }
    return $tableResult;
}

$return = Array('table1' => getTable($conn, 'table1'), 
                'table2' => getTable($conn, 'table2')
          );
$json = json_encode($return,JSON_UNESCAPED_UNICODE);

echo $json;

---

最后：有许多免费的db类可以为您做类似的事情。此外，您可能还想看看REST-API套件，它们也很容易找到，而且是免费的。你正在做的工作，已经做了很多次了，而且大多数都做得更好、更安全。但是如果你还在学习，最好再做一次。

只需将它添加到查询中：

SELECT*FROM table1，table2其中table1.connector=table2.connector ORDER BY table1.id DESC

这就是你需要的吗？但是你的代码只会发送表中的最后一项，因为您在每一行中都覆盖$tem和$json。您的android代码将无法处理多个表。除非它们有相同的字段，但是php需要不同。我们不知道您的表是什么样子。表有相同的字段不适合我我想要喜欢我的代码，因为它可以在android应用程序中与我的json代码一起工作，但如果需要更多表，请告诉我您的特殊需要！请编辑您的问题，您希望json的结构是什么。

public class ListItem_Rewayat {

public String id;
public String name;
public String url;
public String img;
public String num;
public String size;


public String getName() {

    return name;
}

public void setName(String name) {

    this.name = name;
}

public String getid() {

    return id;
}

public void setId(String id1) {

    this.id = id1;
}


public String geturl() {

    return url;
}

public void seturl(String url1) {

    this.url = url1;
}

public String getimg() {

    return img;
}

public void setimg(String img1) {

    this.img = img1;
}

public String getnum() {

    return num;
}

public void setnum(String num1) {

    this.num = num1;
}
public String getsize() {

    return size;
}

public void setsize(String size1) {

    this.size = size1;
}

}

//...
$table1 = Array();
$table2 = Array();
$sql = "SELECT * FROM table1 ORDER BY id DESC";
$result = $conn->query($sql);

if ($result->num_rows >0) {
  // get the result for first table and save it into an array ($table1)
  while($row = $result->fetch_assoc()) {
     $table1[] = $row;
  }
} else {
  echo "0 results";
}

// just do the same for any other table
$sql = "SELECT * FROM table2 ORDER BY id DESC";
$result = $conn->query($sql);

if ($result->num_rows >0) {
  while($row = $result->fetch_assoc()) {
     $table2[] = $row;
  }
} else {
  echo "0 results";
}
// here you put together what you wanna return:
$return = Array('table1' => $table1, 
                'table2' => $table2);
// encode it
$json = json_encode($return,JSON_UNESCAPED_UNICODE);

echo $json;

//...
function getTable($conn, $tableName) {
    $sql = "SELECT * FROM $tableName ORDER BY id DESC";
    $result = $conn->query($sql);
    $tableResult = Array();

    if ($result->num_rows >0) {
       while($row = $result->fetch_assoc()) {
          $tableResult[] = $row;
       }
    }
    return $tableResult;
}

$return = Array('table1' => getTable($conn, 'table1'), 
                'table2' => getTable($conn, 'table2')
          );
$json = json_encode($return,JSON_UNESCAPED_UNICODE);

echo $json;