Question

当用户将记录保存到数据库时，我检查了已保存数据的记录。如果记录已存在于数据库中，请询问用户是否使用消息框覆盖或取消。我想让用户响应OK或取消。

首先，我在运行时从php调用js函数。 JS函数显示确认消息并将返回值传递给隐藏文本框。这部分工作正常。

但是，我无法将文本框值传递给php变量。

＆＃13;

<script>

function confirmOverwrite() {
        var overwriterec = "";
        if(confirm("Do you want to overwrite the record? Click on OK to overwrite.Click Cancel to skip."))
            overwriterec="ok";
        }
        else
        {
            overwriterec="cancel";
        }
        document.getElementById("hiddenVal").value = overwriterec;
}
</script>

＆＃13;

<form action="#" method="post">
    <div>
      <button  type="submit" name="Save"> Save data</button>
	    <input type="text" style="display:none" id="hiddenVal" name="overwrite" />
    </div>
</form>

<?php
if(isset($_POST["Save"])){
$Sql = "SELECT * FROM maintable WHERE userid='$userid'";
$result = mysqli_query($db, $Sql);
                                  
if (mysqli_num_rows($result)>0)
{
   while($row = mysqli_fetch_assoc($result)) 
   {
   
      echo '<script type="text/javascript">',
           'confirmOverwrite();',
           '</script>';           //can call the function and pass the OK or Cancel value to hidden text box.

        if((isset($_POST['overwrite'])) && !empty($_POST['overwrite']))
        {
          $Confirmation = $_POST['overwrite']; //I can't pass the hidden text box value to php variable.
           echo $Confirmation;
         }

         if ($Confirmation == "ok")
         {
           // update the record
         }
   }
  }

}
?>

＆＃13;

Answer 1

您需要在提交之前调用该函数。我添加了一个隐藏价值的警报。

if(isset($_POST["Save"])){
  if((isset($_POST['overwrite'])) && !empty($_POST['overwrite']))
  {
    $Confirmation = $_POST['overwrite']; //I can't pass the hidden text box value to php variable.
    echo $Confirmation
  }
}

＆＃13;

function confirmOverwrite() {
    var overwriterec = "";
    if (confirm('Do you want to overwrite the record? Click on OK to overwrite.Click Cancel to skip.')) {
        overwriterec="ok";
    } else {
        overwriterec="cancel";
    }
    document.getElementById('hiddenVal').value = overwriterec;
    alert(document.getElementById('hiddenVal').value);
}

＆＃13;

<form action="#" method="post" onsubmit="confirmOverwrite()">
    <div>
      <input type="hidden" id="hiddenVal" name="overwrite" />
      <button  type="submit" name="Save"> Save data</button>
    </div>
</form>

＆＃13;

Answer 2

客户端代码：

<html>
<head>
<title>Client Side</title>
</head>
<body>

<script>
function savedata(confirm){
    httpRequest=new XMLHttpRequest();
    httpRequest.open("POST", "savescript.php",true);
    httpRequest.onreadystatechange=saved;
    httpRequest.setRequestHeader("Content-type","application/x-www-form-urlencoded");
    httpRequest.send("confirm="+confirm);
}

function saved(){
    readyState=httpRequest.readyState;
    if(readyState!=4) return;

    httpStatus=httpRequest.status;
    if(httpStatus!=200) return;

    var phpResponse=httpRequest.responseText;

    if(phpResponse==1){ //ask for confirm if the server send back 1
        if(confirm("This record already exists. Are you sure to overwrite this record?")) savedata('yes');
    }
    else savedata('yes');
}
</script>

<p>The example form: </p>
...Other inputs...<br/>
<input type="button" value="Save" onclick="savedata('no')"/>

</body>
</html>

服务器端代码：

<?php
/***********SEVER SIDE CODE (savescript.php)*************/

//Connection to database (mysqli_connect)

$query=mysqli_query($connection_to_db,"your query to check if the record exists");

$confirm=$_POST['confirm']; //the client side confirmation variable

if($confirm=='yes'){ //if the user has confirmed
    //if the record exists update else insert
    if(mysqli_num_row($query)==1) mysqli_query($connection_to_db,"your query to update the record");
    else mysqli_query($connection_to_db,"your query to insert the record");
}
else{   //if the user did not confirm

    if(mysqli_num_row($query)==1) echo("1"); //send 1 this means that the record exists then the client ask for confirm
    else echo("0"); //send 0 this means that the record doesn't exists then you can insert without ask confirm
}
?>

如何在运行时将文本框值传递给php？

2 个答案: