C# 如何在asp.net中访问动态创建的服务器控件
我创建了一个网页,并用于将服务器端控件动态添加到表中 我分别给他们分配了id。。 但我无法访问这些动态创建的服务器控件 C#代码:C# 如何在asp.net中访问动态创建的服务器控件,c#,asp.net,C#,Asp.net,我创建了一个网页,并用于将服务器端控件动态添加到表中 我分别给他们分配了id。。 但我无法访问这些动态创建的服务器控件 C#代码: 受保护的无效页面加载(对象发送方,事件参数e) { 如果(iPostBack) { int num_row=(int)会话[“没有行”]; 对于(int i=2;i
受保护的无效页面加载(对象发送方,事件参数e)
{
如果(iPostBack)
{
int num_row=(int)会话[“没有行”];
对于(int i=2;i
asp代码:
<form id="form1" runat="server">
<div>
<asp:Label ID="Label1" runat="server" Text="textbox value is"></asp:Label>
<asp:Table ID="tbl" runat="server">
<asp:TableRow ID="rw0">
<asp:TableCell ID="c01" Width="100px">
<asp:CheckBox runat="server" ID="chk0" />
</asp:TableCell>
<asp:TableCell ID="c02" Width="100px">
<asp:TextBox runat="server" ID="txt0" />
</asp:TableCell></asp:TableRow>
<asp:TableRow ID="rw1">
<asp:TableCell ID="c11" Width="100px">
<asp:CheckBox ID="chk1" runat="server" />
</asp:TableCell>
<asp:TableCell ID="c12" Width="100px">
<asp:TextBox runat="server" ID="txt1" />
</asp:TableCell></asp:TableRow>
</asp:Table>
<asp:Button ID="btn1" runat="server" Text="Add Row" OnClick="addRow" />
</div>
<asp:Button ID="btnSubmit" runat="server" OnClick="btnSubmit_Click" Text="Submit" />
</form>
请在这方面帮助我。您可以这样做:
TextBox txt= (TextBox)FindControl("txt"+i.Tostring());
string txtValue=txt.Text;
要访问for循环中的所有文本框,请执行以下操作:
int num_row = Convert.ToInt16(sometable.Rows.Count);
for (int i = 1; i < num_row; i++)
{
string txtID="txt" + i.Tostring();
TextBox txt= (TextBox)FindControl(txtID);
string txtValue=txt.Text;
}
int num\u row=Convert.ToInt16(sometable.Rows.Count);
对于(int i=1;i
在每个回帖上,动态创建的控件可能不可见。因此,您需要在每个帖子背面重新创建动态控件。然后您可以访问这些控件 试试看:
tb = (TextBox)sometable.FindControl("txt" + i);
为了测试您的场景,我添加了2个控件txtOutput和Getvalues按钮。除了控件ID从0开始,其中for循环从1开始外,一切似乎都很好 但是,这在FindControl中不应返回null 我怀疑您的表id不正确,因为在您引用的另一篇帖子中,表id是“tbl”。 另一方面,一切似乎都是正确的。不管怎样,我已经粘贴了我在这里尝试过的代码,它很有效 另一种可能会出现错误的情况是,即使在页面加载中创建控件之前,您也尝试访问这些控件。但是,由于表中有两行是静态的,所以无论动态控件的创建如何,代码都应该可以工作。请尝试以下代码并更新
<form id="form1" runat="server">
<div>
<div>
<asp:Table ID="tbl" runat="server">
<asp:TableRow ID="rw0">
<asp:TableCell ID="c01" Width="100px">
<asp:CheckBox runat="server" ID="chk0" />
</asp:TableCell>
<asp:TableCell ID="c02" Width="100px">
<asp:TextBox runat="server" ID="txt0" />
</asp:TableCell></asp:TableRow>
<asp:TableRow ID="rw1">
<asp:TableCell ID="c11" Width="100px">
<asp:CheckBox ID="chk1" runat="server" />
</asp:TableCell><asp:TableCell ID="c12" Width="100px">
<asp:TextBox runat="server" ID="txt1" />
</asp:TableCell></asp:TableRow>
</asp:Table>
<asp:textbox runat="server" id="checkIn" ClientIDMode="Static" name="checkIn" ></asp:textbox>
<asp:Button ID="btn1" runat="server" Text="Add Row" OnClick="addRow" />
<br />
<asp:Button ID="GetValues" runat="server" Text="GetValues" OnClick="GetValuesfromDynamicControls" />
<asp:TextBox ID="txtOutput" runat="server" />
//代码隐藏从这里开始
public partial class DynamicControl : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
if (IsPostBack)
{
int num_row = (int)Session["No_of_Rows"];
for (int i = 2; i < num_row; i++)
{
TableRow row = new TableRow();
TableCell cell1 = new TableCell();
TableCell cell2 = new TableCell();
TextBox tb = new TextBox();
CheckBox cb = new CheckBox();
row.ID = "rw" + i;
cell1.ID = "c" + i + "1";
cell2.ID = "c" + i + "2";
tb.ID = "txt" + i;
tb.EnableViewState = true;
cb.ID = "chk" + i;
cell1.Controls.Add(cb);
cell2.Controls.Add(tb);
row.Cells.Add(cell1);
row.Cells.Add(cell2);
tbl.Rows.Add(row);
}
}
else
{
Session["No_of_Rows"] = 2;
}
}
protected void addRow(object sender, EventArgs e)
{
int num_row = (int)Session["No_of_Rows"];
TableRow row = new TableRow();
TableCell cell1 = new TableCell();
TableCell cell2 = new TableCell();
TextBox tb = new TextBox();
CheckBox cb = new CheckBox();
row.ID = "rw" + num_row;
cell1.ID = "c" + num_row + "1";
cell2.ID = "c" + num_row + "2";
tb.ID = "txt" + num_row;
tb.EnableViewState = true;
cb.ID = "chk" + num_row;
cell1.Controls.Add(cb);
cell2.Controls.Add(tb);
row.Cells.Add(cell1);
row.Cells.Add(cell2);
tbl.Rows.Add(row);
Session["No_of_Rows"] = tbl.Rows.Count;
}
protected void GetValuesfromDynamicControls(object sender, EventArgs e)
{
//int rows =Convert.ToInt32( Session["No_of_Rows"]);
int rows = Convert.ToInt32(tbl.Rows.Count);
StringBuilder sb = new StringBuilder();
for (int i = 0; i < rows; i++)
{
TextBox tb =(TextBox) Page.FindControl("txt" + i);
sb.Append(tb.Text + ";");
}
txtOutput.Text = sb.ToString();
}
}
公共部分类动态控件:System.Web.UI.Page
{
受保护的无效页面加载(对象发送方、事件参数e)
{
如果(iPostBack)
{
int num_row=(int)会话[“没有行”];
对于(int i=2;i public partial class DynamicControl : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
if (IsPostBack)
{
int num_row = (int)Session["No_of_Rows"];
for (int i = 2; i < num_row; i++)
{
TableRow row = new TableRow();
TableCell cell1 = new TableCell();
TableCell cell2 = new TableCell();
TextBox tb = new TextBox();
CheckBox cb = new CheckBox();
row.ID = "rw" + i;
cell1.ID = "c" + i + "1";
cell2.ID = "c" + i + "2";
tb.ID = "txt" + i;
tb.EnableViewState = true;
cb.ID = "chk" + i;
cell1.Controls.Add(cb);
cell2.Controls.Add(tb);
row.Cells.Add(cell1);
row.Cells.Add(cell2);
tbl.Rows.Add(row);
}
}
else
{
Session["No_of_Rows"] = 2;
}
}
protected void addRow(object sender, EventArgs e)
{
int num_row = (int)Session["No_of_Rows"];
TableRow row = new TableRow();
TableCell cell1 = new TableCell();
TableCell cell2 = new TableCell();
TextBox tb = new TextBox();
CheckBox cb = new CheckBox();
row.ID = "rw" + num_row;
cell1.ID = "c" + num_row + "1";
cell2.ID = "c" + num_row + "2";
tb.ID = "txt" + num_row;
tb.EnableViewState = true;
cb.ID = "chk" + num_row;
cell1.Controls.Add(cb);
cell2.Controls.Add(tb);
row.Cells.Add(cell1);
row.Cells.Add(cell2);
tbl.Rows.Add(row);
Session["No_of_Rows"] = tbl.Rows.Count;
}
protected void GetValuesfromDynamicControls(object sender, EventArgs e)
{
//int rows =Convert.ToInt32( Session["No_of_Rows"]);
int rows = Convert.ToInt32(tbl.Rows.Count);
StringBuilder sb = new StringBuilder();
for (int i = 0; i < rows; i++)
{
TextBox tb =(TextBox) Page.FindControl("txt" + i);
sb.Append(tb.Text + ";");
}
txtOutput.Text = sb.ToString();
}
}