Question

我的问题是，1st DropDown中的每个选项都有自己的表，这会触发第二个DropDown菜单，不知怎的，我无法弄清楚如何调用它。所有教程＆amp;我发现的例子中，它们在1st DropDown菜单中触发了一些内容，该菜单位于1表和1之内。第二＆amp; 3rd DropDown可以调用另一个表。（例如：国家，州，市）。

因此，我想知道这是否可行，其中第一个DropDown菜单来自不同的表，第二个DropDown菜单将从第一个DropDown菜单选项中选择填充，第三个DropDown菜单将命令第一个DropDown菜单使用1st DropDown菜单选项。

EDITED

search.html

.....
                    <form id="drop_list" name="drop_list" action="searchedasset.php" method="post" >
                    <fieldset><table><tr>

                    <thead>
                                <tr><legend><b>SEARCH ASSET</b></legend></tr>
                    </thead>
                    <tbody>
                               <tr> <!--code for the first list box-->
                                   <td>Search By :</td>

                                   <td><select name="cat_id" onChange="SelectSubCat1();" >
                                       <Option value="">Choose Search By</option>
                                       </SELECT>
                                   </td>
                               </tr>

                              <tr>
                                  <td>Limit By :</td>
                                  <td><select id="SubCat1" name="SubCat1">
                                      <Option value="">Choose Limit By</option>
                                      </SELECT>
                                  </td>
                              </tr>

                        </tbody>
                        </tr></table></fieldset>
.....

search.js

function fillSearch(){
    // this function is used to fill the category list on load
    addOption(document.drop_list.cat_id, "1", "Brand", "");
    addOption(document.drop_list.cat_id, "2", "Category", "");
    addOption(document.drop_list.cat_id, "3", "Project", "");
}

function SelectSubCat1(){
    // ON selection of category this function will work

    removeAllOptions(document.drop_list.SubCat1);
    //clear all the elements of the second list

    addOption(document.drop_list.SubCat1, "", "Choose Limit By", "");

    if(document.drop_list.cat_id.value == '1'){
        addOption(document.drop_list.SubCat1,"1", "DELL");
        addOption(document.drop_list.SubCat1,"2", "ACER");
        addOption(document.drop_list.SubCat1,"3", "SONY");
        addOption(document.drop_list.SubCat1,"4", "SAMSUNG");
        addOption(document.drop_list.SubCat1,"5", "APPLE");
    }

    if(document.drop_list.cat_id.value == '2'){
        addOption(document.drop_list.SubCat1,"='1'", "Notebook");
        addOption(document.drop_list.SubCat1,"2", "Desktop");
        addOption(document.drop_list.SubCat1,"3", "LCD Projector");
        addOption(document.drop_list.SubCat1,"4", "Scanner");
        addOption(document.drop_list.SubCat1,"5", "Printer");
    }


    if(document.drop_list.cat_id.value == '3'){
        addOption(document.drop_list.SubCat1,"1", "1st Purchase");
        addOption(document.drop_list.SubCat1,"2", "2nd Purchase");
        addOption(document.drop_list.SubCat1,"3", "3rd Purchase");
        addOption(document.drop_list.SubCat1,"4", "4th Purchase");
        addOption(document.drop_list.SubCat1,"5", "5th Purchase");
    }
}

//clear all the elements of the second list
function removeAllOptions(selectbox){
    var i;
    for(i=selectbox.options.length-1;i>=0;i--){
        //selectbox.options.remove(i);
        selectbox.remove(i);
    }
}

//add new options based on the selection of the first drop down box.
function addOption(selectbox, value, text ){
    var optn = document.createElement("OPTION");
    optn.text = text;
    optn.value = value;

    selectbox.options.add(optn);
}

请注意，SubCat1应该来自3个不同名称的表，例如：

[cat_id.value == '1', SubCat1 == 'brandid']
[cat_id.value == '2', SubCat1 == 'categoryid']
[cat_id.value == '3', SubCat1 == 'purchaseid']

因此，这可能吗？有什么方法可以做到吗？要相应地更改SubCat1在数据库中的名称？这是为了在下一页显示数据。谢谢。

在javascript中将变量名声明为php列名

EDITED

0 个答案: