我在textboxs中创建了动态dropdownlist和gridview。它工作得很好。此外，我想在动态dropdownlist中触发事件并执行一些操作。
private ArrayList GetDummyData() {
ArrayList arr = new ArrayList();
arr.Add(new ListItem("Item1", "1"));
arr.Add(new ListItem("Item2", "2"));
arr.Add(new ListItem("Item3", "3"));
arr.Add(new ListItem("Item4", "4"));
arr.Add(new ListItem("Item5", "5"));
return arr;
}
private void FillDropDownList(DropDownList ddl) {
ArrayList arr = GetDummyData();
foreach (ListItem item in arr) {
ddl.Items.Add(item);
}
}
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)));//for TextBox value
dt.Columns.Add(new DataColumn("Column2", typeof(string)));//for TextBox value
dt.Columns.Add(new DataColumn("Column3", typeof(string)));//for DropDownList selected item
dt.Columns.Add(new DataColumn("Column4", typeof(string)));//for DropDownList selected item
dr = dt.NewRow();
dr["RowNumber"] = 1;
dr["Column1"] = string.Empty;
dr["Column2"] = string.Empty;
dt.Rows.Add(dr);
//Store the DataTable in ViewState for future reference
ViewState["CurrentTable"] = dt;
//Bind the Gridview
Gridview1.DataSource = dt;
Gridview1.DataBind();
//After binding the gridview, we can then extract and fill the DropDownList with Data
DropDownList ddl1 = (DropDownList)Gridview1.Rows[0].Cells[3].FindControl("DropDownList1");
DropDownList ddl2 = (DropDownList)Gridview1.Rows[0].Cells[4].FindControl("DropDownList2");
FillDropDownList(ddl1);
FillDropDownList(ddl2);
}
private void AddNewRowToGrid() {
if (ViewState["CurrentTable"] != null) {
DataTable dtCurrentTable = (DataTable)ViewState["CurrentTable"];
DataRow drCurrentRow = null;
if (dtCurrentTable.Rows.Count > 0) {
drCurrentRow = dtCurrentTable.NewRow();
drCurrentRow["RowNumber"] = dtCurrentTable.Rows.Count + 1;
//add new row to DataTable
dtCurrentTable.Rows.Add(drCurrentRow);
//Store the current data to ViewState for future reference
ViewState["CurrentTable"] = dtCurrentTable;
for (int i = 0; i < dtCurrentTable.Rows.Count - 1; i++) {
//extract the TextBox values
TextBox box1 = (TextBox)Gridview1.Rows[i].Cells[1].FindControl("TextBox1");
TextBox box2 = (TextBox)Gridview1.Rows[i].Cells[2].FindControl("TextBox2");
dtCurrentTable.Rows[i]["Column1"] = box1.Text;
dtCurrentTable.Rows[i]["Column2"] = box2.Text;
//extract the DropDownList Selected Items
DropDownList ddl1 = (DropDownList)Gridview1.Rows[i].Cells[3].FindControl("DropDownList1");
DropDownList ddl2 = (DropDownList)Gridview1.Rows[i].Cells[4].FindControl("DropDownList2");
// Update the DataRow with the DDL Selected Items
dtCurrentTable.Rows[i]["Column3"] = ddl1.SelectedItem.Text;
dtCurrentTable.Rows[i]["Column4"] = ddl2.SelectedItem.Text;
}
//Rebind the Grid with the current data to reflect changes
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 = 0; i < dt.Rows.Count; i++) {
TextBox box1 = (TextBox)Gridview1.Rows[i].Cells[1].FindControl("TextBox1");
TextBox box2 = (TextBox)Gridview1.Rows[i].Cells[2].FindControl("TextBox2");
DropDownList ddl1 = (DropDownList)Gridview1.Rows[rowIndex].Cells[3].FindControl("DropDownList1");
DropDownList ddl2 = (DropDownList)Gridview1.Rows[rowIndex].Cells[4].FindControl("DropDownList2");
//Fill the DropDownList with Data
FillDropDownList(ddl1);
FillDropDownList(ddl2);
if (i < dt.Rows.Count - 1) {
//Assign the value from DataTable to the TextBox
box1.Text = dt.Rows[i]["Column1"].ToString();
box2.Text = dt.Rows[i]["Column2"].ToString();
//Set the Previous Selected Items on Each DropDownList on Postbacks
ddl1.ClearSelection();
ddl1.Items.FindByText(dt.Rows[i]["Column3"].ToString()).Selected = true;
ddl2.ClearSelection();
ddl2.Items.FindByText(dt.Rows[i]["Column4"].ToString()).Selected = true;
}
rowIndex++;
}
}
}
}
protected void Page_Load(object sender, EventArgs e) {
if (!Page.IsPostBack) {
SetInitialRow();
}
}
protected void ButtonAdd_Click(object sender, EventArgs e) {
AddNewRowToGrid();
}
protected void Gridview1_RowCreated(object sender, GridViewRowEventArgs e) {
if (e.Row.RowType == DataControlRowType.DataRow) {
DataTable dt = (DataTable)ViewState["CurrentTable"];
LinkButton lb = (LinkButton)e.Row.FindControl("LinkButton1");
if (lb != null) {
if (dt.Rows.Count > 1) {
if (e.Row.RowIndex == dt.Rows.Count - 1) {
lb.Visible = false;
}
}
else {
lb.Visible = false;
}
}
}
}
protected void LinkButton1_Click(object sender, EventArgs e) {
LinkButton lb = (LinkButton)sender;
GridViewRow gvRow = (GridViewRow)lb.NamingContainer;
int rowID = gvRow.RowIndex;
if (ViewState["CurrentTable"] != null) {
DataTable dt = (DataTable)ViewState["CurrentTable"];
if (dt.Rows.Count > 1) {
if (gvRow.RowIndex < dt.Rows.Count - 1) {
//Remove the Selected Row data and reset row number
dt.Rows.Remove(dt.Rows[rowID]);
ResetRowID(dt);
}
}
//Store the current data in ViewState for future reference
ViewState["CurrentTable"] = dt;
//Re bind the GridView for the updated data
Gridview1.DataSource = dt;
Gridview1.DataBind();
}
//Set Previous Data on Postbacks
SetPreviousData();
}
private void ResetRowID(DataTable dt) {
int rowNumber = 1;
if (dt.Rows.Count > 0) {
foreach (DataRow row in dt.Rows) {
row[0] = rowNumber;
rowNumber++;
}
}
}
答案 0 :(得分：0)
可能是问题的副本：
how to add an OnClick event on DropDownList's ListItem that is added dynamically?
请检查那里给出的答案。
DropDownList changesList = new DropDownList();
ListItem item;
item = new ListItem();
item.Text = "go to google.com";
item.Value = "http://www.google.com";
changesList.Items.Add(item);
changesList.Attributes.Add("onChange", "location.href = this.options[this.selectedIndex].value;");
您是否尝试在将新行添加到网格时动态地向事件SelectedIndexChanged添加处理程序？