javascript只获取第一行的变量

javascript only gets the variables of the first row

本文关键字：一行变量获取 javascript 更新时间：2023-09-26

我正在尝试使用下拉列表来"实时"更新表。我只打算在内部使用这个网页。

我真的不太懂javascript，所以我需要一些帮助。

我写的脚本只得到第一行的值，所以实际上不起作用。。。

以下是两页的代码：HTML

<html>
<head>     
<script>
function UpdateUser(str)
{
if (str=="")
  {
  document.getElementById("txtHint").innerHTML="";
  return;
  } 
if (window.XMLHttpRequest)
  {// code for IE7+, Firefox, Chrome, Opera, Safari
  xmlhttp=new XMLHttpRequest();
  }
else
  {// code for IE6, IE5
  xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
  }
xmlhttp.onreadystatechange=function()
  {
  if (xmlhttp.readyState==4 && xmlhttp.status==200)
    {
    document.getElementById("txtHint").innerHTML=xmlhttp.responseText;
    }
  }
    var lastname = document.getElementById('lastname').innerHTML;    
    var firstname = document.getElementById('firstname').innerHTML;                  
    var state = document.getElementById('state').innerHTML;             
    xmlhttp.open("GET","updateuser3.php?q="+str+"&lastname="+lastname+"&firstname="+firstname+"&state="+state,true);
    xmlhttp.send();
}

</script>
</head>
<body>
<?php
$con = mysql_connect('localhost','root','');
if (!$con)
  {
  die('Could not connect: ' . mysql_error($con));
  }

mysql_select_db("test");
$sql="SELECT lastname, firstname, state FROM author";
$result = mysql_query($sql);
echo $sql;
echo "<br />";

echo "<table border='1'>
<tr>
<th>lastname</th>
<th>firstname</th>
<th>State</th>
</tr>";
while($row = mysql_fetch_array($result))
  {
  echo "<tr>";
  echo "<td name='lastname' id='lastname'>" . $row['lastname'] . "</td>";
  echo "<td name='firstname' id='firstname'>" . $row['firstname'] . "</td>";
  echo "<td><select onchange='UpdateUser(this.value)'><option name='state' id='state' value='".$row['state']."'>".$row['state']."</option>"; 
                        if  ($row['state']==='CA')
                            {
                            echo '<option value="OR">OR</option>';
                            echo '<option value="UT">UT</option>';
                            echo '<option value="MI">MI</option>';
                            echo '</select></td>';                                          
                            } 
                            else if ($row['state']==='OR')
                            {                    
                            echo '<option value="CA">CA</option>';
                            echo '<option value="UT">UT</option>';
                            echo '<option value="MI">MI</option>';
                            echo '</select></td>';  
                            }
                            else
                            {
                            echo '<option value="CA">CA</option>';
                            echo '<option value="UT">UT</option>';
                            echo '<option value="MI">MI</option>';
                            echo '<option value="OR">OR</option>';
                            echo '</select></td>';                                  
                            }                  
  echo "</tr>";
  }
echo "</table>";
mysql_close($con);
?>
<br>
<div id="txtHint"><b>State info will be listed here.</b></div>
</body>
</html>

php

<?php
$q=$_GET["q"];
$w=$_GET["lastname"];
$e=$_GET["firstname"];
$r=$_GET["state"];
echo "<br /> New State: ";
echo $q;
echo "<br /> Last Name: ";
echo $w;
echo "<br /> First Name: ";
echo $e;
echo "<br /> Old State: ";
echo $r;
echo "<br />";
$con = mysql_connect('localhost','root','');
if (!$con)
  {
  die('Could not connect: ' . mysql_error($con));
  }

mysql_select_db("test");

$sql = "UPDATE author SET state = '$q' WHERE lastname = '$w' AND firstname = '$e' AND state = '$r'";
echo $sql;
echo "<br />";
mysql_close($con);
?>

有人能帮忙吗？Ty

我会从查询开始进行故障排除，看看您的查询是否返回多个结果。

在MySQL中运行SELECT lastname, firstname, state FROM author查询。

如果这个查询返回多个结果，那么您就知道问题出在您的代码上。

我使用phpMySQL来调试我的SQL。