基於另一個下拉列表的下拉列表，選擇選項來自數據庫

Question

抱歉，如果以前沒有討論過，但是對我來說，所有這些都不起作用。 我有5個下拉菜單，分別是“品牌”，“型號”，“顏色”，“引擎號”和“底盤編號”。我的問題是我應該怎么做才能使模型的下拉列表基於所選的“品牌”下拉列表，例如，如果用戶選擇了“本田”根據我在數據庫中發布的圖像，本田的BrandID為1，因此所有具有BrandID = 1的模型都將顯示。該模型的下拉列表僅具有brandID = 1。 然后，顏色的下拉列表基於模型的下拉列表，因此與我之前討論的邏輯相同。 最后，引擎編號和底盤編號的下拉列表基於顏色的下拉列表，也與我所討論的邏輯相同。

這是我的品牌下拉列表代碼

 <label for="bName" class="control-label col-xs-4"><p class="left">Brand</p></label> <div class="col-xs-7"> <div class="req"> <?php include_once "config.php"; $bsql="SELECT bName, brandID FROM brand order by bName"; $bstmt=$con->prepare($bsql); $bstmt->execute(); $bstmt->bind_result($bName, $bid); $bstmt->store_result(); echo "<select name='brandID' class='form-control'> <option value=''></option>"; while ($bstmt->fetch()){ echo '<option value="'.$bid.'">'.$bName.'</option>'; } echo '</select>'; ?> </div> </div> 

這是模型下拉菜單的代碼

 <label for="model" class="control-label col-xs-4"> <p class="left">Model</p></label> <div class="col-xs-7"> <div class="req"> <?php include_once "config.php"; $msql="SELECT model, modID FROM model order by model"; $mstmt=$con->prepare($msql); //$mstmt->bind_param('i', $bid); $mstmt->execute(); $mstmt->bind_result($model, $mid); $mstmt->store_result(); echo "<select name='mID' class='form-control'> <option value=''></option>"; while ($mstmt->fetch()){ echo '<option value="'.$mid.'">'.$model.'</option>'; } echo '</select>'; ?> </div> </div> 

這是顏色下拉列表的代碼

 <label for="model" class="control-label col-xs-4"><p class="left">Color</p></label> <div class="col-xs-7"> <div class="req"> <?php include_once "config.php"; $csql="SELECT distinct(color) FROM stock order by color"; $cstmt=$con->prepare($csql); $cstmt->execute(); $cstmt->bind_result($color); $cstmt->store_result(); echo "<select name='color' class='form-control'> <option value=''></option>"; while ($cstmt->fetch()){ echo '<option value="'.$color.'">'.$color.'</option>'; } echo '</select>'; ?> </div> </div> 

這是下拉引擎編號的代碼。

 <label for="engNum" class="control-label col-xs-4"> <p class="left">Engine No</p></label> <div class="col-xs-7"> <div class="req"> <?php include_once "config.php"; $esql="SELECT engNum FROM stock where status='Available' order by engNum"; $estmt=$con->prepare($esql); $estmt->execute(); $estmt->bind_result($engNum); $estmt->store_result(); echo "<select name='engNum' class='form-control'> <option value=''></option>"; while ($estmt->fetch()){ echo '<option value="'.$engNum.'">'.$engNum.'</option>'; } echo '</select>'; ?> </div> </div> 

這是下拉框編號的代碼。

 <label for="chassisNum" class="control-label col-xs-4"><p class="left">Chassis No</p></label> <div class="col-xs-7"> <div class="req"> <?php include_once "config.php"; $nsql="SELECT chassisNum FROM stock where status='Available' order by chassisNum"; $nstmt=$con->prepare($nsql); $nstmt->execute(); $nstmt->bind_result($chassisNum); $nstmt->store_result(); echo "<select name='chassisNum' class='form-control'> <option value=''></option>"; while ($nstmt->fetch()){ echo '<option value="'.$chassisNum.'">'.$chassisNum.'</option>'; } echo '</select>'; ?> </div> </div> 

這是我品牌數據庫的圖片

這是我的模型數據庫的圖像

這是顏色的圖像，底盤編號。 和引擎號 數據庫

Answer 1

    Write an onchange event on select tag

    for e.g. to change the Models based on brand selected you should write


    <label for="bName" class="control-label col-xs-4"><p class="left">Brand</p></label>
    <div class="col-xs-7">
        <div class="req">   
        <?php
        include_once "config.php";
        $bsql="SELECT bName, brandID FROM brand order by bName"; 
        $bstmt=$con->prepare($bsql);
        $bstmt->execute();
        $bstmt->bind_result($bName, $bid);
        $bstmt->store_result();

        echo "<select name='brandID' class='form-control' **onchange='getModels(this)'**>
            <option value=''></option>";

            while ($bstmt->fetch()){
                echo '<option value="'.$bid.'">'.$bName.'</option>';
                                }

        echo '</select>';

    //The function getModels(this) will get called whenever user will change the value of the brand option.

    Now define this method in your js file 


    function getModels(BrandObj)
    {
        brandValue=BrandObj.value; // Will give you the ID of brand which is selected.
        // Make A ajax call to some php file which will return models based on brand ID & bind it to your Models Dropdown
    $.ajax({
      url: 'getModels.php',
      type: 'GET', // Method Type 
      data: 'brandID=brandValue',// This parameter will be sent to getModels.php 
      success: function(**data**) {
        //called when successful the data we have returned in getModels.php will be accessible in "data" variable
        // Decode the response & bind it to your dropdownList

      },
      error: function(e) {
        //called when there is an error
        //console.log(e.message);
      }
    });


    }


// IN your getModels.php file write following code

$BrandID=@$_GET['brandID'];
//Connect to database
// Write a sql to find models having brand_id=$BrandID
// Fetch rows & create array of Models & return it using 
echo json_encode(*your_array_name*)

// END getModels.php

    // You can find the detailed documentation of AJAX
    http://api.jquery.com/jquery.ajax/