I am creating a dynamic application. Where I am giving add,update,delete,paging and sorting options. I have one on top drop-down where I am placing table names in option. Problem is that when I select one table and sort it and change the table from drop-down it showing an error that cannot find column A(By which I have done sorting in previous table.)
Here is my code.
protected void gv_Sorting(object sender, GridViewSortEventArgs e)
{
try
{
string sortdir = string.Empty;
if (dir == SortDirection.Ascending)
{
dir = SortDirection.Descending;
sortdir = "Desc";
sortImage.ImageUrl = "../Images/asc.gif";
}
else
{
dir = SortDirection.Ascending;
sortdir = "Asc";
sortImage.ImageUrl = "../Images/desc.gif";
}
DataView sortedView = new DataView(dt);
sortString = e.SortExpression + " " + sortdir;
sortedView.Sort = sortString;
ViewState.Add("View", dt);
ViewState.Add("sortString", sortString);
gv.DataSource = sortedView;
gv.DataBind();
int columnIndex = 0;
foreach (DataControlFieldHeaderCell headerCell in gv.HeaderRow.Cells)
{
if (headerCell.ContainingField.SortExpression == e.SortExpression)
{
columnIndex = gv.HeaderRow.Cells.GetCellIndex(headerCell);
}
}
gv.HeaderRow.Cells[columnIndex].Controls.Add(sortImage);
}
catch (Exception ex)
{
AMP1.Title = "Unable to Get Data.!";
AMP1.Message = ex.Message;
AMP1.MessageDescription = ex.StackTrace;
AMP1.AppMessageType = TEMP.Controls.AplicationMessagePanel.MessageType.Error;
((Button)AMP1.FindControl("btnOK")).CausesValidation = false;
((Button)AMP1.FindControl("btnOK")).Focus();
ModalPopupExtenderException.Show();
}
}
public void createGrid(DataTable dtTable)
{
try
{
// setting flag to get first dropdownlist name
bool flag = true;
dtTable.Columns.Add("SrNo", typeof(String)).SetOrdinal(0);
//Clearing all the columns before adding new one
gv.Columns.Clear();
int count = gv.Columns.Count - 1;
// Creating Columns for the grid
for (int i = 0; i < dtTable.Columns.Count; i++)
{
string colName = dtTable.Columns[i].ColumnName;
TemplateField lname = new TemplateField();
if (HeaderText(colName) != "")
{
lname.HeaderText = HeaderText(colName);// +"<font color='red'>*</font>";
}
else
{
lname.HeaderText = colName;// +"<font color='red'>*</font>"; ;
}
if (colName != "SrNo")
{
lname.SortExpression = colName;
}
if (colName != "ID" && colName != "Active" && colName != "SrNo" && colName != "BModelValue_Val")
{
lname.ItemStyle.CssClass = "tr1";
lname.FooterStyle.CssClass = "tr2";
}
else
{
if (colName == "BModelValue_Val")
{
lname.ItemStyle.CssClass = "tdBeveWorm";
lname.FooterStyle.CssClass = "tdBeveWorm";
}
else
{
lname.ItemStyle.CssClass = "tr1";
lname.FooterStyle.CssClass = "tr2";
}
}
if (colName.EndsWith("_Val") || colName == "ID" || colName == "SrNo")
{
lname.ItemTemplate = new AddTemplateToGrid(AddTemplateToGrid.enumControlType.Label, colName);
if (colName.EndsWith("_Val") && flag == true)
{
firstddl = colName;
flag = false;
}
if (colName != "ID" && colName != "SrNo")
lname.FooterTemplate = new AddTemplateToGrid("footer", AddTemplateToGrid.enumControlType.DropDownList, colName);
}
else
{
if (colName == "Active")
{
lname.ItemTemplate = new AddTemplateToGrid(AddTemplateToGrid.enumControlType.CheckBox, colName);
lname.FooterTemplate = new AddTemplateToGrid("footer", AddTemplateToGrid.enumControlType.CheckBox, colName);
}
else
{
lname.ItemTemplate = new AddTemplateToGrid(AddTemplateToGrid.enumControlType.TextBox, colName);
lname.FooterTemplate = new AddTemplateToGrid("footer", AddTemplateToGrid.enumControlType.TextBox, colName);
}
}
gv.Columns.Add(lname);
}
// Command Buttons for Grid
TemplateField lname1 = new TemplateField();
lname1.HeaderText = "Action";
lname1.ItemTemplate = new AddTemplateToGrid("Item", AddTemplateToGrid.enumControlType.ImageButton, "Action");
lname1.FooterTemplate = new AddTemplateToGrid("footer", AddTemplateToGrid.enumControlType.ImageButton, "Action");
//lname1.FooterStyle.Width = new Unit("150px");
//lname1.ItemStyle.Width = new Unit("150px");
gv.Columns.Add(lname1);
gv.AutoGenerateColumns = false;
// Checking whether page is sorted or not
if (ViewState["View"] != null)
{
DataView dv1 = new DataView(dtTable);
dv1.Sort = ViewState["sortString"].ToString();
// Binding DataView to the Grid
gv.DataSource = dv1;
}
else
{
// Binding DataTable to the Grid
gv.DataSource = dtTable;
}
gv.DataBind();
//Checking Page is having Index or not and setting HiddenField Value.
if (dtTable.Rows.Count > gv.PageSize)
hdfPagindex.Value = "1";
else
hdfPagindex.Value = "0";
}
catch (Exception ex)
{
AMP1.Title = "Unable to Get Data.!";
AMP1.Message = ex.Message;
AMP1.MessageDescription = ex.StackTrace;
AMP1.AppMessageType = TEMP.Controls.AplicationMessagePanel.MessageType.Error;
((Button)AMP1.FindControl("btnOK")).CausesValidation = false;
((Button)AMP1.FindControl("btnOK")).Focus();
ModalPopupExtenderException.Show();
}
}
public void loadTable(string tblName)
{
// Getting Table records
dt = null;
dt = bl.BindDataToMaster(tblName);
// Creating grid according to DataTable
gv.Columns.Clear();
createGrid(dt);
}
protected void ddl_SelectedIndexChanged(object sender, EventArgs e)
{
try
{
ViewState["View"] = null;
ViewState["sortString"] = null;
tblName = ddl.SelectedItem.Value;
gv.PageIndex = 0;
loadTable(tblName);
}
catch (Exception ex)
{
AMP1.Title = "Unable to Get Data.!";
AMP1.Message = ex.Message;
AMP1.MessageDescription = ex.StackTrace;
AMP1.AppMessageType = WEIR_BDK.Controls.AplicationMessagePanel.MessageType.Error;
((Button)AMP1.FindControl("btnOK")).CausesValidation = false;
((Button)AMP1.FindControl("btnOK")).Focus();
ModalPopupExtenderException.Show();
}
} //DropDownList Index Changed
Each Data element in ASP.net has two things, the first one is the DataSource, it's where the data element get the data, and the second one is a method called DataBind, it's a void method, example: Let's assume that my GridView is named grid and the DataTable name dt_table, and the my grid is filled with the data, but my data table is not, so if i want to fill my grid view, i just simply need to add this code :
Greetings.