اسکریپت های جاوا اسکریپت :




    <script>

     function sumation(first,second,third)

     {

first.value=parseInt(second.value)+parseInt(third.  value);

     }

    </script>


کد های Html لازم :





<body>

    <form id="form1" runat="server">

        <div>

            <asp:TextBox ID="m_accepted_1" runat="server" Text="0"></asp:TextBox>+<asp:TextBox ID="f_accepted_1" runat="server" Text="0"></asp:TextBox>

                  

            <asp:TextBox ID="s_accepted_1" runat="server" ></asp:TextBox></div>

    </form>

</body>


کد های سرور ساید :





    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load



        f_accepted_1.Attributes.Add("onkeydown", "sumation(" + s_accepted_1.ClientID + "," + m_accepted_1.ClientID + "," + f_accepted_1.ClientID + ")")

        f_accepted_1.Attributes.Add("onkeyup", "sumation(" + s_accepted_1.ClientID + "," + m_accepted_1.ClientID + "," + f_accepted_1.ClientID + ")")

        m_accepted_1.Attributes.Add("onkeydown", "sumation(" + s_accepted_1.ClientID + "," + m_accepted_1.ClientID + "," + f_accepted_1.ClientID + ")")

        m_accepted_1.Attributes.Add("onkeyup", "sumation(" + s_accepted_1.ClientID + "," + m_accepted_1.ClientID + "," + f_accepted_1.ClientID + ")")



    End Sub

موفق باشی