Bind data to dropdownlist and selectedvalue by C#

Question

I have two table: Category : CatID, CatName News : NewsID, CatID,Title,Content Now, i want, when i edit on table NewS, i have dropdownlist and bind all values from table Category and show SelectedValue previous Please help me

Linh Hoai · Answer

Hi Ramas! It's OKIE. Thank you very much

Rafnas T P · Answer

hi, selected value give category Id from News Table try changing code as shown below try { SqlConnection conn = new SqlConnection(connStr); SqlDataReader reader = null ; conn.Open(); string sql = "SELECT * FROM NEWS where NewsID= " + sid + "" ; SqlCommand comm = new SqlCommand(); comm.Connection = conn; comm.CommandText = sql; reader = comm.ExecuteReader(); while (reader.Read()) { string Newsid = reader.GetValue(reader.GetOrdinal( "Newsid" )).ToString(); string CatID = reader.GetValue(reader.GetOrdinal( "CatID" )).ToString(); string Title = reader.GetValue(reader.GetOrdinal( "Title" )).ToString(); string Content = reader.GetValue(reader.GetOrdinal( "Content" )).ToString(); if (Newsid != "" ) { SqlDataReader reader = null ; string sql = "SELECT CatID, CatName FROM Category order by Catid desc" ; SqlCommand comm = new SqlCommand(); comm.Connection = conn; comm.CommandText = sql; reader = comm.ExecuteReader(); while (reader.Read()) { Dropdownlist.DataSource = reader; Dropdownlist.DataValueField = "CatID" ; Dropdownlist.DataTextField = "CatName" ; Dropdownlist.DataBind(); } Dropdownlist.SelectedValue = CatID ; } }

Linh Hoai · Answer

Hi Jangid! I try your code , but when i show my form, dropdownlist not show value " selected" (Which value of CATID in table NEWS)

Gajendra Jangid · Answer

TRY THIS CODE String str = "cONN STRING HERE" ; SqlConnection con = new SqlConnection(str); SqlCommand cmd = new SqlCommand( "SELECT * FROM NEWS where NewsID = '" + DropDownList1.SelectedValue + "'" , con); SqlDataAdapter Adpt = new SqlDataAdapter(cmd); DataTable dt = new DataTable(); Adpt.Fill(dt); if (dt.Rows.Count > 0) { string Newsid = dt.Rows[0][ "Newsid" ].ToString(); string CatID = dt.Rows[0][ "CatID" ].ToString(); string Title = dt.Rows[0][ "Title" ].ToString(); string Content = dt.Rows[0][ "Content" ].ToString(); if (Newsid != "" ) { string sql = "SELECT CatID, CatName FROM Category order by Catid desc" ; SqlCommand cmd1 = new SqlCommand( sql , con); SqlDataAdapter Adpt1 = new SqlDataAdapter(cmd1); DataTable dt1 = new DataTable(); Adpt1.Fill(dt1); if (dt1.Rows.Count > 0) { string CatID_root = dt.Rows[0][ "CatID" ].ToString(); string CatName = dt.Rows[0][ "CatName" ].ToString(); if (CatID_root == CatID) { Dropdownlist.selectedvalue= CatId; } else { Dropdownlist.DataSource = dt1; Dropdownlist.DataValueField = "CatID" ; Dropdownlist.DataTextField = "CatName" ; Dropdownlist.DataBind(); } } } }

Linh Hoai · Answer

Hi Jangid Here my code , but it fail : try { SqlConnection conn = new SqlConnection(connStr); SqlDataReader reader = null ; conn.Open(); string sql = "SELECT * FROM NEWS where NewsID= " + sid + "" ; SqlCommand comm = new SqlCommand(); comm.Connection = conn; comm.CommandText = sql; reader = comm.ExecuteReader(); while (reader.Read()) { string Newsid = reader.GetValue(reader.GetOrdinal( "Newsid" )).ToString(); string CatID = reader.GetValue(reader.GetOrdinal( "CatID" )).ToString(); string Title = reader.GetValue(reader.GetOrdinal( "Title" )).ToString(); string Content = reader.GetValue(reader.GetOrdinal( "Content" )).ToString(); if (Newsid != "" ) { SqlDataReader reader = null ; string sql = "SELECT CatID, CatName FROM Category order by Catid desc" ; SqlCommand comm = new SqlCommand(); comm.Connection = conn; comm.CommandText = sql; reader = comm.ExecuteReader(); while (reader.Read()) { string CatID_root = reader.GetValue(reader.GetOrdinal( "CatID" )).ToString(); string CatName = reader.GetValue(reader.GetOrdinal( "CatName" )).ToString(); if (CatID_root == CatID) { Dropdownlist.DataSource = reader; Dropdownlist.DataValueField = "CatID" ; Dropdownlist.DataTextField = "CatName" ; Dropdownlist.SelectedValue = CatName; Dropdownlist.DataBind(); } else { Dropdownlist.DataSource = reader; Dropdownlist.DataValueField = "CatID" ; Dropdownlist.DataTextField = "CatName" ; Dropdownlist.DataBind(); } } } }

Gajendra Jangid · Answer

Hii Linh Use like as below: call this function on dropdown change event protected void ddl_selectdvaluechange( object sender, EventArgs e) { SqlConnection con = new SqlConnection(str); SqlCommand cmd = new SqlCommand( "select * from UserDetail where id = '" + DropDownList1.SelectedValue + "'" , con); SqlDataAdapter Adpt = new SqlDataAdapter(cmd); DataTable dt = new DataTable(); Adpt.Fill(dt); GridView1.DataSource = dt; GridView1.DataBind(); } or you can use following links: https://www.c-sharpcorner.com/UploadFile/rohatash/binding-dropdownlist-with-database-and-display-data-in-gridv/ https://www.telerik.com/forums/bind-selectedvalue-after-populating-dropdownlist https://www.aspsnippets.com/Articles/Populate-DropDownList-with-Selected-Value-in-EditItemTemplate-of-GridView-in-ASPNet.aspx https://www.aspsnippets.com/Articles/Populate-DropDownList-with-Selected-Value-in-EditItemTemplate-of-GridView-in-ASPNet.aspx