我有一个GridView,它列出了我的mysql数据库表中的数据。另外,我为GridView创建了两个TemplateFields。第一个TemplateField显示数据库表中的数据,第二个TemplateView包含1x asp:TextBox(又名数量)和2x asp:Buttons(又名+/-按钮,它们会更改数量TextBox内的值)。事件中,我还有一个搜索文本框,用于过滤GridView中显示的行。这是搜索GridView文本框的背后代码:
<asp:GridView id="GridView1" EnableViewState="true" AutoGenerateColumns="false" PageSize="100" ShowHeader="false" DataKeyNames="logic_code" AllowPaging="true" runat="server" Style="width:100%;margin-top:45px;">
<Columns>
<asp:BoundField DataField="QUANTITY" runat="server" readonly="true" />
<asp:TemplateField HeaderText="Product_Template" runat="server">
<ItemTemplate>
<asp:label id="supplier_number" runat="server" Style="font-weight:bold;font-size:28px;" Text='<%# Eval("supplier_number")%>' /> <asp:label id="total_inventory" runat="server" Text='<%# Eval("total_inventory")%>' Style="float:right;" />
<br />
<asp:label id="sequence" runat="server" Text='<%# Eval("sequence")%>' Style="float:right;" />
<br />
<asp:Image id="product_image" runat="server" Height="320px" Width="320px" ImageUrl='<%# Eval("image_location")%>' />
<br />
<asp:label id="product_description" runat="server" Text='<%# Eval("description")%>' Style="white-space:nowrap;" />  <asp:label id="unit_of_price" runat="server" Text='<%# Eval("unit_of_price")%>' Style="float:right;font-size:10px;margin-top:16px;margin-right:5px;margin-left:1px;" /><asp:label id="price_pref" runat="server" Text='<%# "$" + Eval("price_pref")%>' Style="float:right;font-size:22px;font-weight:bold;" />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Product_Template1" runat="server" ItemStyle-Width="150px">
<ItemTemplate runat="server">
<asp:Button id="add" runat="server" Text="+" Width="45px" Style="float:right;" OnClick="addClicked" autopostback="true" UseSubmitBehavior="true"></asp:Button> <asp:Button id="subtract" runat="server" Text="-" Style="float:right;" OnClick="subtractClicked" autopostback="true" UseSubmitBehavior="true" Width="45px"></asp:Button>
<asp:TextBox id="qty_ordered" runat="server" Text="0" Enabled="false" Style="float:right;" Width="57px" EnableViewState="true" ReadOnly="true" />
<asp:Label id="unit_display" runat="server" Style="float:right;" />
<asp:Label id="sequenceID" runat="server" Text='<%# Eval("sequence")%>' Visible="false" Enabled="false" />
<asp:Label id="unit_code1" runat="server" Text='<%# Eval("unit_code")%>' Visible="false" Enabled="false" />
<asp:Label id="supplier_no" runat="server" Text='<%# Eval("supplier_number")%>' Visible="false" Enabled="false" />
<asp:Label id="total_inventory1" runat="server" Text='<%# Eval("total_inventory")%>' Visible="false" Enabled="false" />
<asp:Label id="logic_code1" runat="server" Text='<%# Eval("logic_code")%>' Visible="false" Enabled="false" />
<asp:Label id="unit_of_price1" runat="server" Text='<%# Eval("unit_of_price")%>' Visible="false" Enabled="false" />
<asp:Label id="price_pref1" runat="server" Text='<%# Eval("price_pref")%>' Visible="false" Enabled="false" />
<asp:Label id="special_price1" runat="server" Text='<%# Eval("special_price")%>' Visible="false" Enabled="false" />
<asp:Label id="description1" runat="server" Text='<%# Eval("description")%>' Visible="false" Enabled="false" />
<asp:Label id="tester" runat="server" Text='<%# Eval("description")%>' Visible="false" Enabled="false" />
<asp:Label id="test2" runat="server" Visible="true" Enabled="false" />
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
首先,我尝试将每个行的TextBox.Text保存到ViewState,但是没有成功,然后我尝试在DataBind()之前动态地向DataTable添加新列,但是这又往南走了...按钮(+/-)和当PostBack来自按钮本身时,TextBox可以正常工作。但是,一旦我使用上面的c#代码过滤了GridView,TextBox就会全部变回“ 0”并丢失其值。我认为动态添加新列是一种方法,我只是不确定如何在不创建EditTemplateFields的情况下保存/更新值。
这是我的GridView的asp.net代码:
private void BindGrid()
{
string constr = ConfigurationManager.ConnectionStrings["default"].ConnectionString;
using (MySqlConnection con = new MySqlConnection(constr))
{
con.Open();
using (MySqlCommand cmd = new MySqlCommand("SELECT logic_code,description,image_location,product_group,supplier_number,sequence,unit_code,unit_of_price,location,sales_date,price_pref,special_price,in_stock,total_inventory,new_products FROM products"))
{
using (MySqlDataAdapter da = new MySqlDataAdapter())
{
cmd.Connection = con;
da.SelectCommand = cmd;
using (DataTable dt = new DataTable())
{
da.Fill(dt);
GridView1.DataSource = dt;
dt.Columns.Add(new DataColumn("QUANTITY", System.Type.GetType("System.Double")));
GridView1.DataBind();
con.Close();
}
}
}
}
}
这是当GridView未被搜索框过滤时如何在PageLoad上填充GridView的代码。
protected void Page_Load(object sender, EventArgs e)
{
if (!this.IsPostBack)
{
BindGrid();
}
if (string.IsNullOrEmpty(txtSearch.Text))
{
//txtSearch.Attributes.Add("CssStyle", "cursor");
txtSearch.Attributes.Add("placeholder", " Showing All Products");
}
//foreach(GridViewRow row in GridView1.Rows)
//{
// if (IsPostBack)
// {
// if (ViewState["purchased"].ToString() != null)
// {
// qty.Text = ViewState["purchased"].ToString();
// }
// }
//}
}
PageLoad在这里:
EnableViewState = "true"
页面顶部也有private void SearchProducts()
。
***注意:在每个按钮(+/-)上使用下面的代码,即使通过回发也可以通过读取ViewState正确填充我的标签,因此ViewState似乎可以很好地保存。但是,一旦我调用for(int i = 0; i < GridView1.Rows.Count; i++)
{
Label test222 = (Label)GridView1.Rows[i].FindControl("test2");
TextBox qty2 = (TextBox)GridView1.Rows[i].FindControl("qty_ordered");
ViewState["purchased"] = qty2.Text;
test222.Text = ViewState["purchased"].ToString();
}
render() {
return (
<div>
L'utilisateur <b>{this.state.loggedIn ? "est actuellement" : "n'est pas"}</b> connecté.
</div>
)
}
,这里有两个快照:(如您所见,当我在搜索文本框中输入“ Benus”时,gridview会被正确过滤,但是所有TextBox值都将重置为“ 0”)