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Problem that QR code cannot be generated correctly using phpqrcode
Problem that QR code cannot be generated correctly using phpqrcode
Jul 06, 2016 pm 01:52 PM
Receive the data sent by the client, add this data as a parameter to the URL, and then generate the QR code of this URL. The QR code can be generated, but the URL of the generated QR code does not have the parameters I want.
The code is as follows
<code>$param_str = urldecode($_POST['data']); $param_str = base64_encode($param_str); $url = "http://www.example/order_add.php?data=".$param_str; //url1是將參數(shù)直接寫入U(xiǎn)Rl中 //$url1 = "http://www.example/order_add.php?data=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"; //這個(gè)生成二維碼鏈接中data參數(shù)為空 echo QRcode::png($url); //這樣卻可以生成正確的二維碼 //echo QRcode::png($url1); //$url與$url1恒等比較過為1，兩者編碼相同都為ASCII</code>
It is roughly estimated that there is a problem when the parameters are passed, but I don’t know how to troubleshoot.
In addition, this can also generate the correct QR code
<code>//手動賦值$param_str $param_str = "eyJ1aWQiOiIxMzU5MDE3NjY0N19oaiIsICJtb2JpbGVwaG9uZSI6IjEzNTkwMTc2NDY0IiwgImFyZWEiOiLljJfkuqzluILkuJzln47ljLrkuJzljY7pl6jooZfpgZMiLCAic2hvcExpc3QiOlt7InNob3BQcm9kdWN0ViI6MiwgImFkZGl0aW9uV29yZCI6IiIsICJwb3N0VHlwZSI6MSwgInByaWNlVG90YWwiOjAuMTIsICJwcm9kdWN0TGlzdCI6W3sicHJvZHVjdFZvbHVtZSI6MSwgImNvbWJvSWQiOjAsICJwcm9kdWN0SWQiOjM1fSwgeyJwcm9kdWN0Vm9sdW1lIjoxLCAiY29tYm9JZCI6MCwgInByb2R1Y3RJZCI6NzF9XSwgInNob3BJZCI6MjIsICJwb3N0UHJpY2UiOjAuMH1dLCAiYWRkcmVzcyI6IjY2NjY2NjY2NjY2NjYiLCAiZm9ybUNhcnQiOjEsICJ0ZWxlcGhvbmUiOiJudWxsIiwgImNvbm5lY3ROYW1lIjoiMzMzMzMzMzMzMzMzMzMzMzMzMzMifQ=="; $url = "http://www.example/order_add.php?data=".$param_str; echo QRcode::png($url); //增加路徑 //增加路徑的話會生成實(shí)體的圖片文件，如果有多人同時(shí)訪問，前者就會被覆蓋。所以不適合實(shí)際用 QRcode::png($url,"order_qr.png");*/ </code>
Reply content:
Receive the data sent by the client, add this data as a parameter to the URL, and then generate the QR code of this URL. The QR code can be generated, but the URL of the generated QR code does not have the parameters I want.
The code is as follows
<code>$param_str = urldecode($_POST['data']); $param_str = base64_encode($param_str); $url = "http://www.example/order_add.php?data=".$param_str; //url1是將參數(shù)直接寫入U(xiǎn)Rl中 //$url1 = "http://www.example/order_add.php?data=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"; //這個(gè)生成二維碼鏈接中data參數(shù)為空 echo QRcode::png($url); //這樣卻可以生成正確的二維碼 //echo QRcode::png($url1); //$url與$url1恒等比較過為1，兩者編碼相同都為ASCII</code>
It is roughly estimated that there is a problem when the parameters are passed, but I don’t know how to troubleshoot.
In addition, this can also generate the correct QR code
<code>//手動賦值$param_str $param_str = "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"; $url = "http://www.example/order_add.php?data=".$param_str; echo QRcode::png($url); //增加路徑 //增加路徑的話會生成實(shí)體的圖片文件，如果有多人同時(shí)訪問，前者就會被覆蓋。所以不適合實(shí)際用 QRcode::png($url,"order_qr.png");*/ </code>
Answered it by myself. I only found the wrong place, but not the reason.
This problem is that the client uses JQuery’s $.ajax to pass parameters, causing phpqrcode to be unable to obtain (the server does obtain the data, phpqrcode is the first step of encoding, and the url is correct). If the client Just switch to form submission.
Jquery’s ajax operation does not require urldecode. In fact, urlencode is generally used, and the browser will automatically decode it.
Try to see if this is the reason why you cannot get the parameters.
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