文本框输入,从php中检索数据库而不提交按钮

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<div style="background: rgb(238, 238, 238) none repeat scroll 0% 0%; border: 1px solid rgb(204, 204, 204); padding: 5px 10px; text-align: center;"><span style="color:#008000;"><span style="font-size: 20px;"><span style="font-family: lucida sans unicode,lucida grande,sans-serif;">BOOKS RENEWAL</span></span></span></div>

<p style="text-align: center;">&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp;</p>

<table align="center" border="0" cellpadding="1" cellspacing="1" dir="ltr" height="79" style="height: 400px;" width="580">
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            <td style="white-space: nowrap;"><span style="color:#0000FF;">&nbsp; <span style="font-size: 16px;"><span style="font-family: tahoma,geneva,sans-serif;">Roll Number</span></span></span></td>
            <td colspan="4"><input name="Rollno" type="text" /></td>
        </tr>
        <tr>
            <td style="white-space: nowrap;"><span style="color:#0000FF;"><span style="font-size: 16px;"><span style="font-family: tahoma,geneva,sans-serif;">&nbsp; Name&nbsp;</span></span></span></td>
            <td colspan="4"><input name="Name" type="text" /></td>
        </tr>
        <tr>
            <td style="white-space: nowrap;"><span style="color:#0000FF;"><span style="font-size: 16px;"><span style="font-family: tahoma,geneva,sans-serif;">&nbsp; Branch&nbsp;&nbsp;&nbsp; &nbsp; </span></span></span></td>
            <td><input name="Branch" type="text" /></td>
            <td style="white-space: nowrap;"><span style="color:#0000FF;"><span style="font-size: 16px;"><span style="font-family: tahoma,geneva,sans-serif;">Semester</span></span></span></td>
            <td colspan="2"><input name="Semester" type="text" /></td>
        </tr>
        <tr>
            <td style="white-space: nowrap;"><span style="color:#0000FF;"><span style="font-size: 16px;"><span style="font-family: tahoma,geneva,sans-serif;">&nbsp; Call Number&nbsp;&nbsp;&nbsp;&nbsp;</span></span></span></td>
            <td><input name="Callno" type="text" /></td>
            <td style="white-space: nowrap;"><span style="color:#0000FF;"><span style="font-size: 16px;"><span style="font-family: tahoma,geneva,sans-serif;">Accession Number</span></span></span></td>
            <td colspan="2"><input name="Acc_no" type="text" /></td>
        </tr>
        <tr>
            <td style="white-space: nowrap;"><span style="color:#0000FF;"><span style="font-size: 16px;"><span style="font-family: tahoma,geneva,sans-serif;">&nbsp; Author Name</span></span></span></td>
            <td colspan="4" rowspan="1"><input name="Auth_name" size="69" type="text" /></td>
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            <td style="white-space: nowrap;"><span style="color:#0000FF;"><span style="font-size: 16px;"><span style="font-family: tahoma,geneva,sans-serif;">&nbsp; Title Name&nbsp;&nbsp;&nbsp;</span></span></span></td>
            <td colspan="4" rowspan="1"><input name="title" size="69" type="text" /></td>
        </tr>
        <tr>
            <td style="white-space: nowrap; width: 50px;"><span style="color:#0000FF;"><span style="font-size: 16px;"><span style="font-family: tahoma,geneva,sans-serif;">&nbsp; Date of Issue</span></span></span></td>
            <td colspan="2" rowspan="1" style="white-space: nowrap; width: 300px;"><input name="Date_iss" size="10" type="text" /></td>
            <td rowspan="1" style="white-space: nowrap; width: 50px;"><span style="color:#0000FF;"><span style="font-size: 16px;"><span style="font-family: tahoma,geneva,sans-serif;">Due&nbsp; Date</span></span></span></td>
            <td rowspan="1"><input name="Due_dt" size="10" type="text" /></td>
        </tr>
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            <td style="white-space: nowrap;"><span style="color:#0000FF;"><span style="font-size: 16px;"><span style="font-family: tahoma,geneva,sans-serif;">&nbsp; Due Amount&nbsp;&nbsp;</span></span></span></td>
            <td colspan="2" rowspan="1"><input name="Due_amt" size="5" type="text" /></td>
            <td rowspan="1" style="white-space: nowrap;"><span style="color:#0000FF;"><span style="font-size: 16px;"><span style="font-family: tahoma,geneva,sans-serif;">Amount Paid</span></span></span></td>
            <td rowspan="1"><input name="Amt_paid" size="5" type="text" /></td>
        </tr>
        <tr>
            <td colspan="5" style="white-space: nowrap;"><span style="color:#0000FF;"><span style="font-size: 16px;"><span style="font-family: tahoma,geneva,sans-serif;">&nbsp; Balance</span></span>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp; </span><input name="Balance" size="5" type="text" /></td>
        </tr>
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<p><span style="color:#0000FF;"><span style="font-size: 16px;"><span style="font-family: tahoma,geneva,sans-serif;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></span></span></p>

<p style="text-align: center;"><input name="OK" type="button" value="OK" />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <input name="Exit" type="button" value="Exit" /></p>
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Sir my question is first I will input Rollno and without submit I have to get the details pertaining to rollno from the database without refresh and then In the same page I will input accession number and again I have to get details pertaining to the accession number from the database. This can be done using vb, but If I want to do it in PHP how can I do it.

You can achieve your goal using AJAX. if you don't know about Ajax read here. A solution for the above would be adding the following:

<input name="Rollno" type="text" onblur="myFunction(this.value)" />

suppose you want to input values in

  <input name="Branch" type="text" />

then change it to

 <input name="Branch" type="text" id="change" value=""/>

now the javascript part

 <script>
 function myFunction(r){
 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("change").value= xmlhttp.responseText;
        }
    }
    xmlhttp.open("GET","getdetails.php?roll="+r,true);
    xmlhttp.send();      }
   </script>

now the php part

    if(isset($_GET['roll'])){
  // get the data for roll from the database and simply echo them here;}
       }

this is only a minimal solution to help you understand Ajax.

You can also use jQuery.

<input type="text" id="get">
<div id="result"></div>

your jQuery code.

$("#get").blur(function (){
 var val = $('#get').val();
 $.post('data.php', {value: val}, function (data) {
   $('#result').html(data);
 }
}

in your php file

if(isset($_POST['value'])){
  $results = database query/results
  echo $results;
}