在javascript中abt列表框验证 [英] abt listbox validation in javascript

问题描述

我有一个列表框。现在我想验证列表框以选择最大值5。如果选择的值大于5则应该给出消息。请帮我做这个。也不要选择null值，如果提交没有选择值，那么mssg将会来.plz帮帮我。



谢谢

krupalini

Hi,I have a list box. Now I want to validate listbox to selecting maximum 5 value. If selected value more then 5 it should give message. Please help me to do this.also null value not be select,if submit without selecting value,then mssg wil be come.plz help me.

Thanks
krupalini

推荐答案

你好我完成了。我的解决方案

hello i done that.bellow my solution

<script type="text/javascript" language="javascript">
    function ValidateListBox() {

        var ListBox = document.getElementById('<%=Listbox1.ClientID %>');
        var length = ListBox.length;
        var i = 0;
        var SelectedItemCount = 0;

        for (i = 0; i < length; i++)

         {



            if (ListBox.options[i].selected) {

                SelectedItemCount = SelectedItemCount + 1;

            }

            if (document.getElementById("Listbox1").value == "") {

                alert("warning");

                return false;

            }

            if (SelectedItemCount > 5) {
                alert('More than 5 items selected in listbox.');
                return false;
            }
        }


    }


    </script>

谢谢

krupalini

thanks
krupalini

这篇关于在javascript中abt列表框验证的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！