通过数据库中的ID更新信息-ASP.NET/C#

Question

Thanks for looking at my question in advanced.

I am trying to update information in a database from a save button.

At the moment I have got it saving, but it saves the update as a new row.

I have got the ID of the row that I wish to change but I am struggling to get it to work.

ASP.NET:

<asp:Button runat="server" ID="btnSave" CssClass="btnSubmit" Text="Save" OnClick="btnSave_Click" />

C#:

protected void btnSave_Click(object sender, EventArgs e)
{
    int ItemID = 0;
    var Item = Placements.GetPlacementByExpiry(ItemID, false);
    if (Item == null)
    {
        Item = new Placements();
    }

    Item.CategoryID = Convert.ToInt32(ddlCategory.SelectedValue);
    Item.Title = txtTitle.Text;
    Item.Company = txtCompany.Text;
    Item.Location = txtLocation.Text;
    Item.Duration = txtDuration.Text;
    Item.SalaryFrom = Convert.ToDecimal(txtSalaryFrom.Text);
    Item.SalaryTo = Convert.ToDecimal(txtSalaryTo.Text);
    Item.SalaryType = ddlSalaryType.Text;
    Item.Description = txtDescription.Text;
    Item.Responsibilities = txtResponsibilities.Text;
    Item.Requirements = txtRequirements.Text;
    DateTime ExpiryDate = DateTime.ParseExact(txtExpiryDate.Text, "dd/MM/yyyy", System.Globalization.CultureInfo.InvariantCulture);
    Item.ExpiryDate = ExpiryDate;
    Item.DateCreated = DateTime.Now;

    if (Item.ID == 0)
    {
        Placements.CreatePlacement(Item);
    }
    else
    {
        Placements.UpdatePlacement(Item);
    }

    mvEdit.SetActiveView(vwList);
}

I have tried putting a command argument on the button and changed it in the back end, but receive the following error:

Error   1   No overload for 'btnSave_Click' matches delegate 'System.EventHandler'  C:\Users\laura\Documents\Visual Studio 2010\WebSites\ThirdYearProject\tools\controls\placements\edit.ascx   239

I've been trying to fix it for a while now but I'm not sure what I'm doing wrong! Any help would be appreciated.

Answer 1

I think Item.ID == 0 is not 0 either null or some other values. Please check the value of that.

Answer 2

Is it a typo? Shouldn't this line

btnSave_Click+= new System.EventHandler(this.btnSave_Click);

be moved to the possibly the Page_Load event or even the Pre_Init?

And I think below answer should be help to you

Sample program Event bubbling in Asp.Net