how to set data types in php

How do I setup data types in php, so that only integer or varchar, etc can be entered on a certain textbox. And if an incorrect value is inputted, a script would appear. Please, what's the syntax for this?

    <form name="form1" method="post" action="new.php">
    <td>
    <table width="100%" border="0" cellpadding="3" cellspacing="1" bgcolor="#FFFFFF">
    <tr>
    <td colspan="16" style="background:#9ACD32; color:white; border:white 1px solid; text-align: center"><strong><font size="3">UPDATE IN-PATIENT INFORMATION SHEET</strong></td>
    </tr>
    <tr>

    <td width="54"><font size="3">Hospital #</td>
    <td width="3">:</td>
    <td width="168"><input name="hnum" type="text" id="hospnum"></td>

    <td width="41"><font size="3">Room #</td>
    <td width="3">:</td>
    <td width="168"><input name="rnum" type="text" id="rnum"></td>

    <td width="67"><font size="3">Date</td>
    <td width="3">:</td>
    <td width="168"><input name="adate" type="text" id="adate">

    <td width="67"><font size="3">Time</td>
    <td width="3">:</td>
    <td width="168"><input name="adtime" type="text" id="adtime">

    </td>




    </tr>


    <tr>
    <td><font size="3">Last Name</td>
    <td>:</td>
    <td><input name="lname" type="text" id="lname"></td>
    <td><font size="3">First Name</td>
    <td>:</td>
    <td><input name="fname" type="text" id="fname"></td>
    <td><font size="3">Middle Name</td>
    <td>:</td>
    <td><input name="mname" type="text" id="mname"></td>
    </tr>


    <tr>
    <td><font size="3">Civil Status</td>
    <td>:</td>
    <td><input name="cs" type="text" id="cs"></td>
    <td><font size="3">Age</td>
    <td>:</td>
    <td><input name="age" type="text" id="age"></td>
    <td><font size="3">Birthday</td>
    <td>:</td>
    <td><input name="bday" type="text" id="bday"></td>

    </tr>

    <tr>
    <td><font size="3">Address</td>
    <td>:</td>
    <td><input name="ad" type="text" id="ad"></td>
    <td><font size="3">Telephone #</td>
    <td>:</td>
    <td><input name="telnum" type="text" id="telnum"></td>

    <td width="23"><font size="3">Sex</td>
    <td width="3">:</td>
    <td width="174"><input name="sex" type="text" id="sex"></td>
    </tr>

    <tr>
    <td><font size="3">Pls. Check</td>
    <td>:</td>
    <input type='hidden' name="stats1" value="0">
    <td><input name="stats1" type="checkbox" id="SSS" value="SSS">SSS</td>
    <td><font size="3"></td>
    <td>:</td>
    <input type='hidden' name="stats2" value="0">
    <td><input name="stats2" type="checkbox" id="nonmed" value="NonMedicare">Non Medicare</td>

    <td><font size="3"></td>
    <td>:</td>
    <input type='hidden' name="stats3" value="0">
    <td><input name="stats3" type="checkbox" id="sh" value="stockholder">Stockholder</td>
    </tr>


    <tr>
    <td><font size="3"></td>
    <td></td>
    <input type='hidden' name="stats4" value="0">
    <td><input name="stats4" type="checkbox" id="gsis" value="GSIS">GSIS</td>
    <td><font size="3"></td>
    <td></td>
    <input type='hidden' name="stats5" value="0">
    <td><input name="stats5" type="checkbox" id="senior" value="seniorcitizen">Senior-Citizen</td>


    <tr>
    <td><font size="3"></td>
    开发者_StackOverflow<td></td>
    <input type='hidden' name="stats6" value="0">
    <td><input name="stats6" type="checkbox" id="dep" value="dependent">Dependent</td>
    <td><font size="3"></td>
    <td></td>
    <input type='hidden' name="stats7" value="0">
    <td><input name="stats7" type="checkbox" id="emp" value="employee">Employee</td>
    <td><font size="3"></td>
    <td></td>
    <input type='hidden' name="stats8" value="0">
    <td><input name="stats8" type="text" id="" value="">Others</td>

    </tr>

    <tr>
    <td><font size="3">Admitting/Attending Nurse</td>
    <td>:</td>
    <td><input name="nurse" type="text" id="nurse"></td>

    </tr>






    <tr>

    <td>&nbsp;</td>
    <td>&nbsp;</td>
    <td><input type="submit" name="Submit" value="Search"></td>

    </form>

The code you pasted is for an HTML form. You can use different input types and/or Javascript to control the type of input on the front-end. When the data is POSTed to the back-end you can then use PHP to validate that the form elements entered match the data types you are expecting.

I could be wrong but I believe in your new.php page you would have to verify each of the fields you want manually.

Check out:

http://www.phpro.org/tutorials/Validating-User-Input.html