网上购物系统（Task009）——FormView插入删除商品详细信息

一、进入插入模板

1、protectedvoid fvwItemDetails_ModeChanging(object sender,FormViewModeEventArgs e)函数中添加代码：

case FormViewMode.Insert:

this.fvwItemDetails.ChangeMode(FormViewMode.Insert);

break;

2、此时，可进入插入模板，不过，不显示任何信息，也不能够获得下拉列表框的句柄，须添加PreRender()消息响应函数，在这个消息响应函数中添加填充下拉列表框的代码：

protected void fvwItemDetails_PreRender(object sender,EventArgs e)

{

if (fvwItemDetails.CurrentMode ==FormViewMode.Insert)

{

DropDownList ddl = (DropDownList)fvwItemDetails.FindControl("ddlCategories");

if (ddl != null)

{

BindDropDownList(ddl);

}

二、修改BindDropDownList()函数

[csharp] private void BindDropDownList(DropDownList ddl)
{
    ddl.DataSource = new Category().GetCategories();
    ddl.DataTextField = "Name";
    ddl.DataValueField = "CategoryId";
    ddl.DataBind();

    if (ViewState["SelectedCategoryId"] != null)
    {
        ListItem selectedItem = ddl.Items.FindByValue(ViewState["SelectedCategoryId"].ToString());
        if (selectedItem != null)
            selectedItem.Selected = true;
    }
    else
    {
        string selectcategory = Request.QueryString["categoryId"].ToString();
        ListItem selectedItem = ddl.Items.FindByValue(selectcategory);
        if (selectedItem != null)
            selectedItem.Selected = true;
    }
}
private void BindDropDownList(DropDownList ddl)
{
    ddl.DataSource = new Category().GetCategories();
    ddl.DataTextField = "Name";
    ddl.DataValueField = "CategoryId";
    ddl.DataBind();

    if (ViewState["SelectedCategoryId"] != null)
    {
        ListItem selectedItem = ddl.Items.FindByValue(ViewState["SelectedCategoryId"].ToString());
        if (selectedItem != null)
            selectedItem.Selected = true;
    }
    else
    {
        string selectcategory = Request.QueryString["categoryId"].ToString();
        ListItem selectedItem = ddl.Items.FindByValue(selectcategory);
        if (selectedItem != null)
            selectedItem.Selected = true;
    }
}

三、添加消息响应函数fvwItemDetails_ItemInserting()

[csharp] protected void fvwItemDetails_ItemInserting(object sender, FormViewInsertEventArgs e)
{
    ItemDetails itemdetails = new ItemDetails();
    if (ViewState["ImageUrl"] != null)
    {
        itemdetails.Image = ViewState["ImageUrl"].ToString();
    }

    if (ViewState["SelectedCategoryId"] != null)
    {

        DropDownList ddl = (DropDownList)fvwItemDetails.FindControl("ddlCategories");
        itemdetails.CategoryId = ViewState["SelectedCategoryId"].ToString();
    }

    TextBox txtname = (TextBox)fvwItemDetails.FindControl("txtName");
    itemdetails.Name = txtname.Text;

    TextBox txtPrice = (TextBox)fvwItemDetails.FindControl("txtPrice");
    itemdetails.Price = decimal.Parse(txtPrice.Text);

    TextBox txtDescn = (TextBox)fvwItemDetails.FindControl("txtDescn");
    itemdetails.Descn = txtDescn.Text;

    TextBox txtSupplyTime = (TextBox)fvwItemDetails.FindControl("txtSupplyTime");
    itemdetails.SupplyTime = txtSupplyTime.Text;

    TextBox txtSupplyDate = (TextBox)fvwItemDetails.FindControl("txtSupplyDate");
    itemdetails.SupplyDate = txtSupplyDate.Text;

    TextBox txtSupplyArea = (TextBox)fvwItemDetails.FindControl("txtSupplyArea");
    itemdetails.SupplyArea = txtSupplyArea.Text;

    Item item = new Item();
    item.InsertItem(itemdetails);

    fvwItemDetails.ChangeMode(FormViewMode.ReadOnly);

    BindFormView();
    ViewState["ImageUrl"] = null;
    ViewState["SelectedCategoryId"] = null;

}
protected void fvwItemDetails_ItemInserting(object sender, FormViewInsertEventArgs e)
{
    ItemDetails itemdetails = new ItemDetails();
    if (ViewState["ImageUrl"] != null)
    {
        itemdetails.Image = ViewState["ImageUrl"].ToString();
    }

if (ViewState["SelectedCategoryId"] != null)
{

        DropDownList ddl = (DropDownList)fvwItemDetails.FindControl("ddlCategories");
        itemdetails.CategoryId = ViewState["SelectedCategoryId"].ToString();
    }

TextBox txtname = (TextBox)fvwItemDetails.FindControl("txtName");
itemdetails.Name = txtname.Text;

TextBox txtPrice = (TextBox)fvwItemDetails.FindControl("txtPrice");
itemdetails.Price = decimal.Parse(txtPrice.Text);

TextBox txtDescn = (TextBox)fvwItemDetails.FindControl("txtDescn");
itemdetails.Descn = txtDescn.Text;

TextBox txtSupplyTime = (TextBox)fvwItemDetails.FindControl("txtSupplyTime");
itemdetails.SupplyTime = txt

补充：Web开发 , ASP.Net ,