PHP超级简单问题，50分

Question

<!--购买数量-->
         <div class='buyinfo'>
         <table width='auto'>
            <tr>
               <td><span>购买数量：</span></td>
               <td> <div class="Numinput">
                    <input type="text" name="goods[num]" size="5" value=1 />
                    <span  class="numadjust increase"></span>
                    <span  class="numadjust decrease"></span>
                    </div>
               </td>
               <td> <span <{if !$showStorage}>style='display:none;'<{/if}>>&nbsp;&nbsp;(库存<span class='store'><{if $goods.store >= 9999 || $goods.store == null || $goods.store === ''}>9999+<{else}><{$goods.store}><{/if}></span>)</span></td>
            </tr>
         </table>
         </div> 
<!--购买数量结束-->
    </div><!-- end hightbox-->
  </div><!-- end hightline-->
在现有的基础上如果限制用户的输入只能是4或者4的倍数？然后怎么加到源代码里产生作用？？最好详细点，本人对B/S程序一窍不通，谢谢了。

Answer 1

用Javascript捕捉客户端用户的操作，如果输入数字完毕，验证是否满足要求即可

Answer 2

Javascript  也不会啊，谁帮弄弄啊

Answer 3

JSfunction judge(){
 var input=document.getElementById("num").value;
     if(input%4==0){ 
    
}else{
alert("你的输入不正确,只能输入4或4的倍数");
}
}HTMLdiv class='buyinfo'> 
        <table width='auto'> 
            <tr> 
              <td> <span>购买数量： </span> </td> 
              <td> <div class="Numinput"> 
                    <input type="text" name="goods[num]" size="5"  id="num" onchange="judge()" /> 
                    <span  class="numadjust increase"> </span> 
                    <span  class="numadjust decrease"> </span> 
                    </div> 
              </td> 
              <td> <span <{if !$showStorage}>style='display:none;' <{/if}>>&nbsp;&nbsp;(库存 <span class='store'> <{if $goods.store >= 9999 || $goods.store == null || $goods.store === ''}>9999+ <{else}> <{$goods.store}> <{/if}> </span>) </span> </td> 
            </tr> 
        </table> 
        </div> 
<!--购买数量结束--> 
    </div> <!-- end hightbox--> 
  </div> <!-- end hightline--> 

Answer 4

监听输入框onblur事件,然后验证
<input type="text" name="goods[num]" size="5" value=1 onblur='validate()'/> 

Answer 5

<input type="text" id='num' name="goods[num]" size="5" value=1 onblure='test()'/>用onblur事件也可以的

Answer 6

对啊，好象是ecshop,3楼的可以不啊

Answer 7

3楼的javaScript脚本放哪里执行啊？

Answer 8

JS，就放你HTML的代码里。
function judge(){
 var input=document.getElementById("num").value; 
if(input%4==0){ }else{ 
alert("你的输入不正确,只能输入4或4的倍数");
 }
 }<div class='buyinfo'> 
        <table width='auto'> 
            <tr> 
              <td> <span>购买数量： </span> </td> 
              <td> <div class="Numinput"> 
                    <input type="text" name="goods[num]" size="5"  id="num" onchange="judge()" /> 
                    <span  class="numadjust increase"> </span> 
                    <span  class="numadjust decrease"> </span> 
                    </div> 
              </td> 
              <td> <span <{if !$showStorage}>style='display:none;' <{/if}>>&nbsp;&nbsp;(库存 <span class='store'> <{if $goods.store >= 9999 || $goods.store == null || $goods.store === ''}>9999+ <{else}> <{$goods.store}> <{/if}> </span>) </span> </td> 
            </tr> 
        </table> 
        </div> 
<!--购买数量结束--> 
    </div> <!-- end hightbox--> 
  </div> <!-- end hightline--> 

Answer 9

<script>function judge(){
 var input=document.getElementById("num").value; 
if(input%4==0){ }else{ 
alert("你的输入不正确,只能输入4或4的倍数");
 }
 }</script><div class='buyinfo'> 
        <table width='auto'> 
            <tr> 
              <td> <span>购买数量： </span> </td> 
              <td> <div class="Numinput"> 
                    <input type="text" name="goods[num]" size="5"  id="num" onchange="judge()" /> 
                    <span  class="numadjust increase"> </span> 
                    <span  class="numadjust decrease"> </span> 
                    </div> 
              </td> 
              <td> <span <{if !$showStorage}>style='display:none;' <{/if}>>&nbsp;&nbsp;(库存 <span class='store'> <{if $goods.store >= 9999 || $goods.store == null || $goods.store === ''}>9999+ <{else}> <{$goods.store}> <{/if}> </span>) </span> </td> 
            </tr> 
        </table> 
        </div> 
<!--购买数量结束--> 
    </div> <!-- end hightbox--> 
  </div> <!-- end hightline--> 
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