使用PHP下拉框

Question

I have a drop down box it pulls values from db.It will display only one column in drop down box.If i select one column in drop down box,it should display other values in text box.

I have done displaying values in drop down box but i am struck here.If i select a value in drop down corresponding values has to be displayed in text box

eg: car bmw classc 125hp

here if i select bmw in drop down box i should get that class c and 125ho in text box.

Answer 1

you could store your display value in an attribute - eg data-text

  <select id="car">
    <option name="none" data-text="" value="">---</option>
    <option name="bmw" data-text="class c" value="bmw">bmw</option>
    <option name="ford" data-text="4 door" value="ford">ford</option>
  </select>

  <input type="text" id="display"/>

you can update the text field as follows (if you are using jquery)

​$()​.ready(function() {

  $("#car").bind("change", function() {
     $("#display").val($("#car :selected").attr("data-text"))
  })
})​

I put a live example at - http://jsbin.com/ifefo4

Answer 2

PHP works server-side, it processes your web site when requested by the client, then sends the result page to the client. For instance, your drop box is filled on the server and sent to the client.

Selecting an item in the drop box, however, is done in the client's browser. Alas, the server does not know about it, hence there is no way for your PHP script to react to this (unless you force a refresh of the site everytime the user changes the dropbox item, which would be an extremely bad concept).

You will need to work with a script type that works on the client end, JavaScript is most common here. A JavaScript can react on a drop box selection and fill in the data in your text fields accordingly.

Note, however, that the JavaScript on the client side has no access to any server resources, say texts from your database. Those resources would have to be inserted into the JavaScript by your PHP script so they get sent over to the client as well.

Answer 3

You must use a Javascript for client-side.

Make a javascript array that you fill with the values for the textbox. Then on the onchange method for the dropbox you reload the content in the textbox from this array.