我的 pdf 转换显示什么都没有..但我在 mysql.. (fpdf) 中有数据

Question

我的代码在这里 ;

 require('pdf_creat/fpdf.php');
     include ('class/db.php');

    $pdf=new FPDF();
    $pdf->AddPage();
    $pdf->SetFont('Arial','B',10);
    $pdf->Ln();
    $pdf->Ln();
    $pdf->SetFont('times','B',10);
    $pdf->Cell(25,7,"Stud ID");
    $pdf->Cell(30,7,"Student Name");
    $pdf->Cell(40,7,"Address");
    $pdf->Cell(30,7,"Class");
    $pdf->Cell(30,7,"Phone No");
    $pdf->Cell(30,7,"E-mail");
    $pdf->Ln();
    $pdf->Cell(450,7,"----------------------------------------------------------------------------------------------------------------------------------------------------------------------");
    $pdf->Ln();

    $sql = "select * from students";
    $result = dbConnect()->prepare($sql);

    $row=$result->fetchAll(PDO::FETCH_ASSOC);

    while($rows=array_shift($row)) {                               
        $studid = $rows[0];
        $name = $rows[1];
        $address = $rows[2];
        $class = $rows[3];
        $phone = $rows[4];
        $email = $rows[5];
        $pdf->Cell(25,7,$studid);
        $pdf->Cell(30,7,$name);
        $pdf->Cell(40,7,$address);
        $pdf->Cell(30,7,$class);
        $pdf->Cell(30,7,$phone);
        $pdf->Cell(30,7,$email); 
        $pdf->Ln();                  
    }
    $pdf->Output();

我只做了系统，但是当我显示时，它什么也没显示。我想在 mysql 中显示数据。我的代码有什么错误吗？我搜索了很多答案，但他们都不让我满意。如果我有任何错误或者我必须在我的代码之间添加任何功能，请任何人告诉我？

Answer 1

因为，我不知道 include('class/db.php');包含。我使用 PDO 连接来测试你的情况：

require('fpdf.php');



function getConnection() {
    $dbhost='localhost';
    $dbuser='root';
    $dbpass='';
    $dbname='testdb';
    $dbh = new PDO("mysql:host=$dbhost;dbname=$dbname", $dbuser, $dbpass);
    $dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
    return $dbh;
}




$pdf=new FPDF();

$pdf->AddPage();
$pdf->SetFont('Arial','B',10);
$pdf->Ln();
$pdf->Ln();
$pdf->SetFont('times','B',10);
$pdf->Cell(25,7,"Stud ID");
$pdf->Cell(30,7,"Student Name");
$pdf->Cell(40,7,"Address");
$pdf->Cell(30,7,"Class");
$pdf->Cell(30,7,"Phone No");
$pdf->Cell(30,7,"E-mail");
$pdf->Ln();
$pdf->Cell(450,7,"----------------------------------------------------------------------------------------------------------------------------------------------");
$pdf->Ln();

$sql = "select * from   students";

$db = getConnection();
$stmt = $db->query($sql);
$rows = $stmt->fetchAll(PDO::FETCH_ASSOC);
$db = null;

foreach($rows as $key=>$value){

    $studid = $value['studid'];
    $name = $value['name'];
    $address = $value['address'];
    $class = $value['class'];
    $phone = $value['phone'];
    $email = $value['email'];
    $pdf->Cell(25,7,$studid);
    $pdf->Cell(30,7,$name);
    $pdf->Cell(40,7,$address);
    $pdf->Cell(30,7,$class);
    $pdf->Cell(30,7,$phone);
    $pdf->Cell(30,7,$email);
    $pdf->Ln();
}
$pdf->Output();

唯一的主要变化是 i 在 pdo 关联数组上循环的方式。我正在访问从数据库读取的每一行的键，所以而不是

$studid = $rows[0];

我正在访问说出 id

$studid = $rows['id'];

我的 pdf 转换显示什么都没有..但我在 mysql.. (fpdf) 中有数据

my pdf convert show nothing.. but i have datas in mysql.. (fpdf)

php

mysql

fpdf