wangtian Posted April 6, 2011 Share Posted April 6, 2011 hi, I want to calculate selectbox value in a form. for example: item price * Quantity. it's works fine if it only have one calculation in the form. function calculate(){document.calcform.total.value =(document.calcform.Chassis.value)*(document.calcform.Quantity.value) } howerver, when when I have more than one calculation, it gives me "NaN.00" here is the function calculate(){ document.calcform.total.value = (document.calcform.Motherboard.value)*(document.calcform.Quantity.value)+(document.calcform.Chassis.value)*(document.calcform.Quantity1.value) } I also posted a picture about the result. Anyone can help me to fix it? I appreciate it. here is all my code on the page: <html> <head> <title> </title> <style type = "text/css"> .SelectClass { font-size: 15px; } table { font-size: .9em; border: 3px groove; padding: 0px; background-color: #dddddd; } .mycss { font-weight:normal;font-style:italic;color:#000000;letter-spacing:1pt;word-spacing:2pt;font-size:36px;text-align:left;font-family:courier new, courier, monospace;line-height:1; } </style> <script LANGUAGE="JavaScript"> function dp(price) { string = "" + price; number = string.length - string.indexOf('.'); if (string.indexOf('.') == -1) return string + '.00'; if (number == 1) return string + '00'; if (number == 2) return string + '0'; if (number > 3) return string.substring(0,string.length-number+3); return string; } function calculate(){ document.calcform.total.value = dp((document.calcform.Motherboard.value)*(document.calcform.Quantity.value)+(document.calcform.Chassis.value)*(document.calcform.Quantity1.value)) } </script> </head> <body onload="calculate"> <div class="mycss"><center>Order List</center></div><br /> <center> <form name="calcform" method="post" action="test2.php"> <table border="0" width="800"> <tr> <td align="right" colspan="2"> <font size="6">$</font><input name="total" style="border:0px solid #000000; background-color:#E6FBF4; font-size: 25.5px;" type="text" value="0.00" ONCHANGE="calculate()"/> </td></tr> <tr> <td><font size="+1"> Product Name</font> </td> <td><font size="+1">Quantity</font></td></tr> <td colspan="2"> <?php mysql_connect("host", "user", "pass") or die(mysql_error()); mysql_select_db("a4202648_wang") or die(mysql_error()); echo "<table width='100%'>"; echo "<tr><td align='left' width='90%'>"; $result = mysql_query("SELECT Motherboard_Part_Number, Motherboard_Name, Motherboard_Price FROM Motherboard where Motherboard_Part_Number='MB-435ED-3'") or die(mysql_error()); echo '<select id="Motherboard" class="SelectClass" name="Motherboard" ONCHANGE="calculate()">'; // keeps getting the next row until there are no more to get while($row = mysql_fetch_array( $result )) { // Print out the contents of each row into a table echo '<option Name="Motherboard" value= ',$row['Motherboard_Price'],'>',$row['Motherboard_Part_Number'],' ',$row['Motherboard_Name'],' $',$row['Motherboard_Price'],' ','</option>'; } echo '</select>'; echo "</td>"; echo "<td align='right' width='10%'>"; $result= mysql_query("SELECT Number FROM Quantity") or die(mysql_error()); echo '<select id="Quantity" class="SelectClass" name="Quantity" Value="Quantity" ONCHANGE="calculate()" >'; // keeps getting the next row until there are no more to get while($row = mysql_fetch_array( $result)) { // Print out the contents of each row into a table echo '<option value=',$row['Number'],'>',$row['Number'],'</option>'; } echo '</select>'; echo "</td></tr>"; echo "<tr><td align='left' width='90%'>"; $result = mysql_query("SELECT Chassis_Part_Number, Chassis_Name, Chassis_Price FROM Chassis where Chassis_Form_Factor='ATX'") or die(mysql_error()); echo '<select id="Chassis" class="SelectClass" name="Chassis" ONCHANGE="calculate()">'; // keeps getting the next row until there are no more to get while($row = mysql_fetch_array( $result )) { // Print out the contents of each row into a table echo '<option Name="Chassis" value= ',$row['Chassis_Price'],'>',$row['Chassis_Part_Number'],' ',$row['Chassis_Name'],' $',$row['Chassis_Price'],' ','</option>'; } echo '</select>'; echo "</td>"; echo "<td align='right' width='10%'>"; $result= mysql_query("SELECT Number FROM Quantity") or die(mysql_error()); echo '<select id="Quantity" class="SelectClass" name="Quantity1" Value="Quantity" ONCHANGE="calculate()" >'; // keeps getting the next row until there are no more to get while($row = mysql_fetch_array( $result)) { // Print out the contents of each row into a table echo '<option value=',$row['Number'],'>',$row['Number'],'</option>'; } echo '</select>'; echo "</td></tr>"; echo "</table>"; ?> </td> </tr> <tr><td colspan="2"><input type="submit" /></td></tr> </table> </form> </center> </body> </html> [attachment deleted by admin] Quote Link to comment Share on other sites More sharing options...
Pikachu2000 Posted April 6, 2011 Share Posted April 6, 2011 When posting code, please post it within . . . BBCode tags. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.