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近期有需求是:前端签名后结合平台协议生成签名文件

本例实现方法为:借助canvas生成签名图片,然后贴至协议底部保存为pdf文档

(本例在TP6环境下)借助TCPDF实现  官方提供多个例子点击查看

第一步: 引入组件

composer

composer require tecnickcom/tcpdf

或github直接下载导入

GitHub - tecnickcom/TCPDF: Official clone of PHP library to generate PDF documents and barcodes
放置于vendor下

/**
     * 生成签名文档
     * @param int $sign_id // 签名图片ID
     * @param int $accordId // 协议ID
     * @return void
     * @throws DataNotFoundException
     * @throws DbException
     * @throws ModelNotFoundException
     */
    public function saveSign(int $sign_id=0, int $accordId=10007)
    {
        if(!$sign_id){
            return ;
        }
        $signUrl = (new UploadFile())->find($sign_id);//获取签名图片路径
        if(empty($signUrl) || empty($signUrl->preview_url)){
            return ;
        }
        $signUrl = $signUrl->preview_url;
        if(!file_exists('pdf')){
            mkdir('pdf');
        }
        if(file_exists('pdf/'.$sign_id.'.pdf')){
            return ;
        }

        $pdf = new \TCPDF(PDF_PAGE_ORIENTATION, PDF_UNIT, PDF_PAGE_FORMAT, true,'UTF-8', false);
        $pdf->setCreator(PDF_CREATOR);
        $pdf->setAuthor('Nicola Asuni');
        $pdf->setTitle('TCPDF Example 002');
        $pdf->setSubject('TCPDF Tutorial');
        $pdf->setKeywords('TCPDF, PDF, example, test, guide');

        $pdf->setPrintHeader(false);
        $pdf->setPrintFooter(false);

        $pdf->setDefaultMonospacedFont(PDF_FONT_MONOSPACED);

        $pdf->setMargins(PDF_MARGIN_LEFT, PDF_MARGIN_TOP, PDF_MARGIN_RIGHT);

        $pdf->setAutoPageBreak(TRUE, PDF_MARGIN_BOTTOM);

        $pdf->setImageScale(PDF_IMAGE_SCALE_RATIO);

        // droidsansfallback 中文字符 需额外引用放至vendor/tecnickcom/tcpdf/fonts
        $pdf->setFont('droidsansfallback', '', 14);

        $pdf->AddPage();

        $center = (new Help()) -> find($accordId); // 协议内容
        $txt = <<<EOD
$center->content
EOD;
        $pdf->writeHTMLCell(0, 0, '', '', $txt, 0, 1, 0, true, '', true);

        $pdf->Image($signUrl, '', '', 35, 20, '', '', 'B', false, 300, 'R', false, false, 1, false, false, false);
        $pdf->writeHTMLCell(0, 0, '', '', date('Y年m月d日'), 0, 1, 0, true, 'R', true);

        ob_clean(); // 可不加
        $pdf->Output($_SERVER['DOCUMENT_ROOT'].'pdf/'.$sign_id.'.pdf', 'F');
    }

效果如下

注: 需引入droidsansfallback解决中文乱码问题