C# 未在文本框中添加值
我在本教程中找到了以下代码: Default.aspxC# 未在文本框中添加值,c#,asp.net,gridview,viewstate,C#,Asp.net,Gridview,Viewstate,我在本教程中找到了以下代码: Default.aspx <asp:gridview ID="Gridview1" runat="server" ShowFooter="true" AutoGenerateColumns="false"> <Columns> <asp:BoundField DataField="RowNumber" HeaderText="Row Number
<asp:gridview ID="Gridview1" runat="server" ShowFooter="true"
AutoGenerateColumns="false">
<Columns>
<asp:BoundField DataField="RowNumber" HeaderText="Row Number" />
<asp:TemplateField HeaderText="Header 1">
<ItemTemplate>
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Header 2">
<ItemTemplate>
<asp:TextBox ID="TextBox2" runat="server"></asp:TextBox>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Header 3">
<ItemTemplate>
<asp:TextBox ID="TextBox3" runat="server"></asp:TextBox>
</ItemTemplate>
<FooterStyle HorizontalAlign="Right" />
<FooterTemplate>
<asp:Button ID="ButtonAdd" runat="server" Text="Add New Row" onclick="ButtonAdd_Click" />
</FooterTemplate>
</asp:TemplateField>
</Columns>
</asp:gridview>
Default.aspx.cs
protected void Page_Load(object sender, EventArgs e){
if (!Page.IsPostBack){
SetInitialRow();
}
}
private void SetInitialRow(){
DataTable dt = new DataTable();
DataRow dr = null;
dt.Columns.Add(new DataColumn("RowNumber", typeof(string)));
dt.Columns.Add(new DataColumn("Column1", typeof(string)));
dt.Columns.Add(new DataColumn("Column2", typeof(string)));
dt.Columns.Add(new DataColumn("Column3", typeof(string)));
dr = dt.NewRow();
dr["RowNumber"] = 1;
dr["Column1"] = string.Empty;
dr["Column2"] = string.Empty;
dr["Column3"] = string.Empty;
dt.Rows.Add(dr);
//Store the DataTable in ViewState
ViewState["CurrentTable"] = dt;
Gridview1.DataSource = dt;
Gridview1.DataBind();
}
private void AddNewRowToGrid(){
int rowIndex =0;
if (ViewState["CurrentTable"] != null)
{
DataTable dtCurrentTable = (DataTable)ViewState["CurrentTable"];
DataRow drCurrentRow = null;
if (dtCurrentTable.Rows.Count > 0)
{
for (int i = 1; i <= dtCurrentTable.Rows.Count; i++)
{
//extract the TextBox values
TextBox box1 = (TextBox)Gridview1.Rows[rowIndex].Cells[1].FindControl("TextBox1");
TextBox box2 = (TextBox)Gridview1.Rows[rowIndex].Cells[2].FindControl("TextBox2");
TextBox box3 = (TextBox)Gridview1.Rows[rowIndex].Cells[3].FindControl("TextBox3");
drCurrentRow = dtCurrentTable.NewRow();
drCurrentRow["RowNumber"] = i + 1;
drCurrentRow["Column1"] = box1.Text;
drCurrentRow["Column2"] = box2.Text;
drCurrentRow["Column3"] = box3.Text;
rowIndex++;
}
//add new row to DataTable
dtCurrentTable.Rows.Add(drCurrentRow);
//Store the current data to ViewState
ViewState["CurrentTable"] = dtCurrentTable;
//Rebind the Grid with the current data
Gridview1.DataSource = dtCurrentTable;
Gridview1.DataBind();
}
}
else
{
Response.Write("ViewState is null");
}
//Set Previous Data on Postbacks
SetPreviousData();
}
private void SetPreviousData(){
int rowIndex = 0;
if (ViewState["CurrentTable"] != null)
{
DataTable dt = (DataTable)ViewState["CurrentTable"];
if (dt.Rows.Count > 0)
{
for (int i = 1; i < dt.Rows.Count; i++)
{
TextBox box1 = (TextBox)Gridview1.Rows[rowIndex].Cells[1].FindControl("TextBox1");
TextBox box2 = (TextBox)Gridview1.Rows[rowIndex].Cells[2].FindControl("TextBox2");
TextBox box3 = (TextBox)Gridview1.Rows[rowIndex].Cells[3].FindControl("TextBox3");
box1.Text = dt.Rows[i]["Column1"].ToString();
box2.Text = dt.Rows[i]["Column2"].ToString();
box3.Text = dt.Rows[i]["Column3"].ToString();
rowIndex++;
}
}
}
}
protected void ButtonAdd_Click(object sender, EventArgs e){
AddNewRowToGrid();
}
受保护的无效页面加载(对象发送方,事件参数e){
如果(!Page.IsPostBack){
SetInitialRow();
}
}
私有void SetInitialRow(){
DataTable dt=新的DataTable();
数据行dr=null;
添加(新的数据列(“行数”,typeof(字符串));
Add(新的数据列(“Column1”,typeof(string));
Add(新的数据列(“Column2”,typeof(string));
Add(新的数据列(“Column3”,typeof(string));
dr=dt.NewRow();
dr[“行数”]=1;
dr[“Column1”]=string.Empty;
dr[“Column2”]=string.Empty;
dr[“Column3”]=string.Empty;
dt.Rows.Add(dr);
//将数据表存储在ViewState中
视图状态[“当前表”]=dt;
Gridview1.DataSource=dt;
Gridview1.DataBind();
}
私有void AddNewRowToGrid(){
int rowIndex=0;
如果(ViewState[“CurrentTable”]!=null)
{
DataTable dtCurrentTable=(DataTable)视图状态[“CurrentTable”];
DataRow drCurrentRow=null;
如果(dtCurrentTable.Rows.Count>0)
{
对于(int i=1;i 0)
{
对于(int i=1;i
现在的问题是,假设当初始网格出现时,我添加一些数据,然后单击“添加行”。我在该行中添加的数据保持不变。但是现在,假设我添加了5行,然后转到第3行,添加一些数据,然后单击“添加行”,该数据将消失,并且永远不会显示。只有在最后一行添加数据时,数据才会显示然后单击“添加行”。有人知道为什么会发生这种情况吗?由于这个循环,它正在发生:
for (int i = 1; i <= dtCurrentTable.Rows.Count; i++)
{
//extract the TextBox values
TextBox box1 = (TextBox)Gridview1.Rows[rowIndex].Cells[1].FindControl("TextBox1");
TextBox box2 = (TextBox)Gridview1.Rows[rowIndex].Cells[2].FindControl("TextBox2");
TextBox box3 = (TextBox)Gridview1.Rows[rowIndex].Cells[3].FindControl("TextBox3");
drCurrentRow = dtCurrentTable.NewRow();
drCurrentRow["RowNumber"] = i + 1;
drCurrentRow["Column1"] = box1.Text;
drCurrentRow["Column2"] = box2.Text;
drCurrentRow["Column3"] = box3.Text;
rowIndex++;
}
因此,drCurrentRow
的内容是最后一行
更新:
为了解决这个问题,我建议您这样做,一次只能添加一行,然后不要循环遍历数据表中的所有行,只需从最后一行获取数据,并将其用作要添加到数据表的“新”行的数据,如下所示:
//extract the TextBox values
TextBox box1 = (TextBox)Gridview1.Rows[dtCurrentTable.Rows.Count - 1].Cells[1].FindControl("TextBox1");
TextBox box2 = (TextBox)Gridview1.Rows[dtCurrentTable.Rows.Count - 1].Cells[2].FindControl("TextBox2");
TextBox box3 = (TextBox)Gridview1.Rows[dtCurrentTable.Rows.Count - 1].Cells[3].FindControl("TextBox3");
drCurrentRow = dtCurrentTable.NewRow();
drCurrentRow["RowNumber"] = dtCurrentTable.Rows.Count + 1;
drCurrentRow["Column1"] = box1.Text;
drCurrentRow["Column2"] = box2.Text;
drCurrentRow["Column3"] = box3.Text;
//add new row to DataTable
dtCurrentTable.Rows.Add(drCurrentRow);
按钮在哪里单击
?如何调用addNewRowtGrid
按钮?它位于页脚按钮的onclick事件上template@P.Brian.Mackey-在发布代码的最底部。@BradHazelnut-我建议这样做,一次只能将一行添加到网格中。而不是遍历所有行,只需使用数据表中最后一项的数据来填充“新”行。请参阅我的答案中的UPDATE:
。
//extract the TextBox values
TextBox box1 = (TextBox)Gridview1.Rows[dtCurrentTable.Rows.Count - 1].Cells[1].FindControl("TextBox1");
TextBox box2 = (TextBox)Gridview1.Rows[dtCurrentTable.Rows.Count - 1].Cells[2].FindControl("TextBox2");
TextBox box3 = (TextBox)Gridview1.Rows[dtCurrentTable.Rows.Count - 1].Cells[3].FindControl("TextBox3");
drCurrentRow = dtCurrentTable.NewRow();
drCurrentRow["RowNumber"] = dtCurrentTable.Rows.Count + 1;
drCurrentRow["Column1"] = box1.Text;
drCurrentRow["Column2"] = box2.Text;
drCurrentRow["Column3"] = box3.Text;
//add new row to DataTable
dtCurrentTable.Rows.Add(drCurrentRow);