需要javascript来在下拉列表中调用隐藏值

Question

i have 2 dropdown list , warehouse and location(called as subwarehouse in my coding).

the warehouse is the parent and location is the child. what i want is that eg, when a user clicks on warehouse ddl, this results will show:

• Singapore
• Malaysia
• Thailand

as user clicks on [singapore], location will show:

• Woodlands
• Sembawang

**how do i make my location show results of warehouse selected?

 function einv_generateWarehouseDropdown($warehouse,$field,$subwarehouse)
    {
        //connect to database
        base_connectDatabase();
        echo "<select id=\"".$field."\" name=\"".$field."\"  style=\"width:300px\" onChange=\"getSubjDesc(this.value);showSubWarehouseDetails(this.value)\" onfocus=\"getSubjDesc(this.value);showSubWarehousehouseDetails(this.value)\">";

        //if (isset($warehouse)) {
        if (isset($warehouse) && ($warehouse != "")) {
            $warehousename = einv_getWarehouseDetail($warehouse);
            echo "<option value=\"". $warehouse ."\">". $warehousename['einv_wh_name'] ."</option>";
        } else {
            $warehouse = 0;
        }

        $getWarehouseSQL = base_executeSQL("SELECT * FROM einv_warehouse where einv_wh_id<>" . $warehouse . " 
        ORDER BY einv_wh_name");
        while($warehousedata_row = base_fetch_array($getWarehouseSQL)){
            if (base_num_rows($getWarehouseSQL)!= 0) {
                echo "<option value=\"". $warehousedata_row['einv_wh_id'] ."\">". $warehousedata_row['einv_wh_name']."</option>";
            }
        }
        echo  "</select>";

        $subwarehouse = "";
        $getSubWarehouseSQL = base_executeSQL("SELECT * FROM einv_subwarehouse  ORDER BY einv_whs_name");
        while($subwarehousedata_row = base_fetch_array($getSubWarehouseSQL)){
            if (base_num_rows($getSubWarehouseSQL)!= 0) {
                $subwarehouse.="<input type=hidden name='lstsubj_DESC_".$subwarehousedata_row['einv_whs_wh_id']."[]' id='lstsubj_DESC_".$subwarehousedata_row['einv_whs_id']."' value='".$subwarehousedata_row['einv_whs_id']."|||".$subwarehousedata_row['einv_whs_name']."'>
";
                //$subwarehouse.="<input type=hidden name='lstcomp_DESC_".$subwarehousedata_row['einv_whs_wh_id']."[]' id='lstcomp_DESC_".$subwarehousedata_row['einv_whs_id']."' value='".$subwarehousedata_row['einv_whs_id']."'>
";
            }
        }
        echo $subwarehouse;

        //close the database
        base_closeDatabase();
    }

    function einv_generateSubWarehouseDropdown($subwarehouse,$field)
    {
        //connect to database
        base_connectDatabase();

        $subwarehouse = NULL;
        echo "<select id=\"".$field."\" name=\"".$field."\"  style=\"width:200px\">";
    //  onChange=\"getSubjDesc(this.value);showSubWarehouseDetails(this.value)\" onfocus=\"getSubjDesc(this.value);showSubWarehousehouseDetails(this.value)\">";


        if (isset($subwarehouse))
        {
            $subwarehousename = einv_getSubWarehouseDetail($subwarehouse);
            echo "<option value=\"". $subwarehouse ."\">". $subwarehousename['einv_whs_name'] ."</option>";
            //$subwarehouse.="<input type=hidden name='lstsubj_DESC_".$subwarehouse."' id='lstsubj_DESC_".$subwarehouse."' value='".$subwarehousename['einv_whs_name']."'>
";
            //$subwarehouse.="<input type=hidden name='lstcomp_DESC_".$subwarehouse."' id='lstcomp_DESC_".$subwarehouse."' value='".$subwarehousename['einv_whs_id']."'>
";
        }elseif(!isset($subwarehouse))
        {
            $subwarehouse = 0;
        }
        echo "SELECT * FROM einv_subwarehouse where einv_whs_id<>" . $subwarehouse . " 
        ORDER BY einv_whs_name";
        $getSubWarehouseSQL = base_executeSQL("SELECT * FROM einv_subwarehouse where einv_whs_id<>". $subwarehouse . " 
        ORDER BY einv_whs_name");
             while($subwarehousedata_row = base_fetch_array($getSubWarehouseSQL))
             if (base_num_rows($getSubWarehouseSQL)!= 0)
             {
                 echo "<option value=\"". $subwarehousedata_row['einv_whs_id'] ."\">". $subwarehousedata_row['einv_whs_name']."</option>";
                // $subwarehouse.="<input type=hidden name='lstsubj_DESC_".$subwarehousedata_row['einv_whs_id']."' id='lstsubj_DESC_".$subwarehousedata_row['einv_whs_id']."' value='".$subwarehousedata_row['einv_whs_name']."'>
";
                // $subwarehouse.="<input type=hidden name='lstcomp_DESC_".$subwarehousedata_row['einv_whs_id']."' id='lstcomp_DESC_".$subwarehousedata_row['einv_whs_id']."' value='".$subwarehousedata_row['einv_whs_id']."'>
";
             }
        echo  "</select>";
        echo $subwarehouse;


        //close the database
        base_closeDatabase();
        }

Answer 1

You would probably need Ajax for that chained feature. A simple method for doing it without ajax is using data attribute:

<select id="parent">
    <option value="1">Parent 1</option>
</select>

<select id="child">
    <option data-parentid="1">Child 1 from Parent 1</option>
</select>

Then you perform a change event to show or hide the desired child options.

Code omitted for brevity. Check it out on Fiddle.

By the way, this is just an example. You have to implement it on your code. Good luck.