如何将以下事件转换为javascript？

Question

I am in confusion how to do, is there a way?

Below is my code. Is there a possible way to call a method inside JavaScript, because I have a method named GetTaxDetails() in the event.

protected void ddlTaxCode_SelectedIndexChanged(object sender, EventArgs e)
{
    try
    {

        decimal taxvalue = 0;
        decimal rate = 0;
        if (txtRate.Text != "")
        {
         rate = Convert.ToDecimal(txtRate.Text);
        }
        string Taxcode = ddlTaxCode.SelectedValue.ToString();
        DataSet dsTaxDetails = new DataSet();
        objTax.TXCode = Taxcode;
        dsTaxDetails = objTax.GetTaxDetails();
        txtCalcType.Text = dsTaxDetails.Tables[0].Rows[0][4].ToString();
        decimal IncludeValue = Convert.ToDecimal(dsTaxDetails.Tables[0].Rows[0][3].ToString());
        string Calculation = Session["TaxCalcType"].ToString();
        if (Calculation == "Exclude")
        {
            txtValue.Text = IncludeValue.ToString();

            if (txtCalcType.Text == "P-Perc")
            {
                taxvalue = IncludeValue * (rate / 100);
            }
            else
            {
                taxvalue = IncludeValue;
            }
            txtTaxValue.Text = taxvalue.ToString();
            txtItemRate.Text = (taxvalue + rate).ToString();
        }
        else
        {
            decimal IncludedTaxValue = (100 + IncludeValue) / 100;
            txtValue.Text = IncludedTaxValue.ToString();

            if (txtCalcType.Text == "P-Perc")
            {
                taxvalue = rate - (rate / IncludedTaxValue);
            }
            else
            {
                taxvalue = IncludeValue;
            }
            txtTaxValue.Text = taxvalue.ToString();
            txtItemRate.Text = (rate - taxvalue).ToString();
        }
    }
    catch (Exception)
    {
        Response.Redirect("Error.aspx");
    }
}

Answer 1

Since you want to access objTax that is not accessable for your client until you do a post back, I recommend the asp:UpdatePanel :

Use the ASP.NET Ajax build-in by wrapping your relating controls into an asp:UpdatePanel . Make sure to place a asp:ScriptManager below your <form> tag, too.

http://msdn.microsoft.com/library/bb398864(v=vs.100).aspx