Hi, I am getting the following error:
Object reference not set to an instance of an object.
When I intially run the page it displays a list of databases as per attached '*.jpg' file.
Then I am able to select a database name and it displays the corresponding tables.
But, when I then select a table name it gives the error described below:
The complete code is as per attached code snippet.
Thanks in Advance.
Line 117: {
Line 118: Response.Write("dbTableNam
Line 119: dbTableName = Request.QueryString["table
Line 120: }
Line 121: string oMyString = null;
d:\aaaWebaaa\assignmentWeb
Screen displaying databases and tables
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it does not like line 119
dbTableName = Request.QueryString["table
sometimes line 114
odbName = Request.QueryString["db"].
How can I combine the two requests?
In the main page can I do the following:
<a href="cmsSchema.aspx?db=<%#
<a href="cmsSchema.aspx?table
As suggested made alterations to code and it has stopped bombing.
Thanks for the help.
I just need to now display the data from selected table.
The alteration as suggested is below:
if (Request.QueryString["db"]
{
Response.Write("odbName:" + odbName + " ");
odbName = Request.QueryString["db"].
}
if (Request.QueryString["tabl
{
Response.Write("dbTableNam
dbTableName = Request.QueryString["table
}
Hi,
I have tried as suggested:
<a href="<% ="cmsSchema.aspx?db=" + DataBinder.Eval(Container.
in place of:
<a href="cmsSchema.aspx?db=<%#
I get the following error:
The name 'Container' does not exist in the current context.
Do you have any further ideas? Many Thanks in advance.
Do you mean in the main aspx page.
<asp:Repeater id="Repeater1" runat="server">
<HeaderTemplate>
</HeaderTemplate>
<ItemTemplate>
<a href="cmsSchema.aspx?db=<%#
<%# DataBinder.Eval(Container.
</ItemTemplate>
<FooterTemplate>
</FooterTemplate>
</asp:Repeater><br />
<asp:Repeater runat="server" ID="repTest">
<ItemTemplate>
<a href="cmsSchema.aspx?table
<%# DataBinder.Eval(Container.
code behind page:
//************************
//cmsSchema.aspx.cs Code behind Page
//************************
using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.
using System.Xml.Linq;
using System.Data.SqlClient;
using System.Data.Common;
using System.IO;
using System.Text;
using System.Drawing;
using System.Data.OleDb;
public partial class cmsSchema : System.Web.UI.Page
{
public string sSql;
public string sDir;
public bool bDatabaseExists = false;
public bool bTableExists = false;
public string sDBServer = System.Net.Dns.GetHostName
public string cboSQLServers = System.Net.Dns.GetHostName
public string sDataSource = "fuertemon";
public object sDBServerProvider = "\\sqlexpress";
public string sUSERid = "sa";
public string sDBName = "Master";
public string sDBPass = "h6web97";
public string TempTable = "Employ";
public string TempProcedure = "UpdateEmployDetails";
public string strTable;
public string strProcedure;
public SqlConnection connection;
public string ConnectionString;
public string MsgBoxDatabase = null;
public string MsgBoxTable = null;
public string MessageBox = null;
public string MessageBoxProcedure = null;
public DataView Source;
public DataSet Ds;
public string sOutput;
public string strResponse;
public int i;
public string tablePage;
public string dbName;
public string strCountdb;
public string dbTableName;
public string oTableName;
public string strTbleCount;
public string odbName;
public string odbTableName;
protected void Page_Load(object sender, System.EventArgs e)
{
HttpContext _Context = HttpContext.Current;
if (Page.IsPostBack)
{
}
if (!Page.IsPostBack)
{
BindGrid();
}
//************************
//Response.Write("1#" + Request["tablePage"]);
LabelPage.Text = (Request["tablePage"]);
//************************
SqlConnection sConn = null;
SqlDataReader sReader = null;
SqlCommand sComm = null;
string sMyString = null;
Session["connStringValue"]
sMyString = Session["connStringValue"]
sConn = new System.Data.SqlClient.SqlC
sComm = new System.Data.SqlClient.SqlC
try
{
sConn.Open();
sReader = sComm.ExecuteReader();
Repeater1.DataSource = sReader;
Repeater1.DataBind();
sReader.Close();
}
catch (Exception ex)
{
// all other .NET exceptions
Labelerr.Text = ex.ToString();
}
catch
{
// all other exceptions
}
finally
{
if (sConn.State != ConnectionState.Closed)
{
sConn.Close();
}
}
//************************
Init();
//testDatabase_SelectedInd
//************************
if (Request.QueryString["db"]
{
Response.Write("odbName:" + odbName + " ");
odbName = Request.QueryString["db"].
}
if (Request.QueryString["tabl
{
Response.Write("dbTableNam
dbTableName = Request.QueryString["table
}
string oMyString = null;
SqlDataReader odbreader = null;
SqlCommand odbcomm = null;
int oCounter = 0;
Session["connStringValue"]
oMyString = Session["connStringValue"]
SqlConnectionStringBuilder
SqlConnection odbconn = new SqlConnection(builder.Conn
odbconn.Open();
DataTable tblDatabases = odbconn.GetSchema(SqlClien
odbconn.Close();
ArrayList oItems = new ArrayList();
ArrayList data = new ArrayList();
foreach (DataRow rowDatabase in tblDatabases.Rows)
{
if (!(string.IsNullOrEmpty(ro
{
builder.InitialCatalog = rowDatabase["table_name"].
odbconn.ConnectionString = builder.ConnectionString;
oItems.Add(rowDatabase["ta
//hs.Add("Inv#", "001");
data.Add(KV("Table:", rowDatabase["table_name"].
}
oCounter += 1;
}
odbconn = new System.Data.SqlClient.SqlC
if (odbconn.State != ConnectionState.Closed)
{
odbconn.Close();
}
//grid.DataSource = oItems;
//grid.DataBind();
repTest.DataSource = data;
repTest.DataBind();
//Session["oItems"] = oItems;
//Session["oCounter"] = oCounter;
//************************
//************************
SqlConnection oconn = null;
SqlDataReader reader2 = null;
SqlCommand ocomm = null;
bool First = false;
string sqlstmt = null;
Session["connStringValue"]
//oMyString = Session["connStringValue"]
oMyString = Session["connStringValue"]
oconn = new System.Data.SqlClient.SqlC
//ocomm = new System.Data.SqlClient.SqlC
ocomm = new System.Data.SqlClient.SqlC
try
{
oconn.Open();
reader2 = ocomm.ExecuteReader();
Hashtable TypeTable = new Hashtable();
object[] array = new object[101];
var counter = 0;
while (reader2.Read())
{
TypeTable.Add(reader2["Col
array[counter] = reader2["Column_Name"];
counter += 1;
}
reader2.Close();
}
catch (Exception ex)
{
// all other .NET exceptions
Labelerr.Text = ex.ToString();
}
catch
{
// all other exceptions
}
finally
{
if (oconn.State != ConnectionState.Closed)
{
oconn.Close();
}
}
//************************
}
// KV for KeyValue is defined as returning an anonymous object:
private object KV(string Key, string Value)
{
return new { Key, Value };
}
private static new void Init()
{
// initiate variables etc
}
protected override void OnInit(EventArgs e)
{
//MyBase.OnInit(e);
//Converted event handler wireups:
Load += Page_Load;
//AddHandler DropDownList1.SelectedInde
//AddHandler DropDownList1.SelectedInde
//AddHandler grid.SelectedIndexChanged,
//AddHandler empDetails.PageIndexChangi
//AddHandler empDetails.ModeChanging, AddressOf empDetails_ModeChanging
//AddHandler empDetails.ItemUpdating, AddressOf empDetails_ItemUpdating
//AddHandler empDetails.ItemUpdated, AddressOf empDetails_ItemUpdated
}
public void BindGrid()
{
//************************
//************************
}
protected void grid_SelectedIndexChanged(
{
//************************
//************************
}
}
The first one gives error:
the name 'DataItem' does not exist in current context
<a href="<% ="cmsSchema.aspx?db=" + DataBinder.Eval(DataItem, "name") +"&tableName=" + DataBinder.Eval(DataItem, "Value")%>">
The second gives error:
No overload for method 'Eval' takes '1' arguments.
<a href="<% ="cmsSchema.aspx?db=" + DataBinder.Eval( "name") +"&tableName=" + DataBinder.Eval( "Value")%>">
I have used findcontrol only as follows:
I am not familiar in their use as per your suggestion.
Is it possible to give an example, then I might be able to figure it out.
Once again, many thanks.
// Read the employee from the DetailsView object
int employeeId = (int)employeeDetails.DataK
// Find the TextBox controls with updated data
TextBox newAddressTextBox =
(TextBox)employeeDetails.F
TextBox newCityTextBox =
(TextBox)employeeDetails.F
// Extract the updated data from the TextBoxes
string newAddress = newAddressTextBox.Text;
string newCity = newCityTextBox.Text;
// Define data objects
SqlConnection conn;
SqlCommand comm;
// Initialize connection
string connectionString =
I have tried the suggestion with my second repeater.
I get two errors:
error:1: no overload for method 'Add' takes 1 argument.
hsh.Add(KV("Table:", rowDatabase["table_name"].
error:2: 'ASP.app_cmsschema_aspx' does not contain a definition for 'repTest_ItemCreated' and no extension method 'repTest_ItemCreated' accepting a first argument of type 'ASP.app_cmsschema_aspx' could be found (are you missing a using directive or an assembly reference?)
My code so far is as follows:
*.aspx
<asp:Repeater ID="repTest" runat="server"
onitemcreated="repTest_Ite
<ItemTemplate>
<asp:HyperLink ID="HyperLink1" runat="server">HyperLink</as
</ItemTemplate>
</asp:Repeater>
*.aspx.cs
string oMyString = null;
SqlDataReader odbreader = null;
SqlCommand odbcomm = null;
int oCounter = 0;
Session["connStringValue"]
oMyString = Session["connStringValue"]
SqlConnectionStringBuilder
SqlConnection odbconn = new SqlConnection(builder.Conn
odbconn.Open();
DataTable tblDatabases = odbconn.GetSchema(SqlClien
odbconn.Close();
ArrayList oItems = new ArrayList();
Hashtable hsh = new Hashtable();
foreach (DataRow rowDatabase in tblDatabases.Rows)
{
if (!(string.IsNullOrEmpty(ro
{
builder.InitialCatalog = rowDatabase["table_name"].
odbconn.ConnectionString = builder.ConnectionString;
oItems.Add(rowDatabase["ta
//hs.Add("Inv#", "001");
hsh.Add(KV("Table:", rowDatabase["table_name"].
}
oCounter += 1;
}
odbconn = new System.Data.SqlClient.SqlC
if (odbconn.State != ConnectionState.Closed)
{
odbconn.Close();
}
repTest.DataSource = hsh;
repTest.DataBind();
Also code as follows:
protected void repTest_ItemCommand(object
{
//************************
if (e.Item.ItemType == ListItemType.Item ||
e.Item.ItemType == ListItemType.AlternatingIt
{
HyperLink hl = (HyperLink)e.Item.FindCont
if (hl != null)
{
hl.NavigateUrl = "cmsSchema.aspx?" + ((DictionaryEntry)e.Item.D
}
}
//************************
}
// KV for KeyValue is defined as returning an anonymous object:
private object KV(string Key, string Value)
{
return new { Key, Value };
}
curred 1 error:
<asp:Repeater ID="repTest" runat="server"
OnItemCommand="repTest_Ite
<ItemTemplate>
<asp:HyperLink ID="HyperLink1" runat="server">HyperLink</as
</ItemTemplate>
</asp:Repeater>
protected void repTest_ItemCommand1(objec
{
//************************
if (e.Item.ItemType == ListItemType.Item ||
e.Item.ItemType == ListItemType.AlternatingIt
{
HyperLink hl = (HyperLink)e.Item.FindCont
if (hl != null)
{
hl.NavigateUrl = "cmsSchema.aspx?" + ((DictionaryEntry)e.Item.D
}
}
//************************
}
// KV for KeyValue is defined as returning an anonymous object:
private object KV(string Key, string Value)
{
return new { Key, Value };
}
Still one error:
string oMyString = null;
SqlDataReader odbreader = null;
SqlCommand odbcomm = null;
int oCounter = 0;
Session["connStringValue"]
oMyString = Session["connStringValue"]
SqlConnectionStringBuilder
SqlConnection odbconn = new SqlConnection(builder.Conn
odbconn.Open();
DataTable tblDatabases = odbconn.GetSchema(SqlClien
odbconn.Close();
ArrayList oItems = new ArrayList();
Hashtable hsh = new Hashtable();
foreach (DataRow rowDatabase in tblDatabases.Rows)
{
if (!(string.IsNullOrEmpty(ro
{
builder.InitialCatalog = rowDatabase["table_name"].
odbconn.ConnectionString = builder.ConnectionString;
oItems.Add(rowDatabase["ta
//hsh.Add("Inv#", "001");
hsh.Add("1", "1");
hsh.Add("2", "1");
hsh.Add("3", "1");
hsh.Add("4", "1");
hsh.Add("5", "1");
//hsh.Add(KV("Table:", rowDatabase["table_name"].
}
oCounter += 1;
}
odbconn = new System.Data.SqlClient.SqlC
if (odbconn.State != ConnectionState.Closed)
{
odbconn.Close();
}
repTest.DataSource = hsh;
repTest.DataBind();
second error:
Item has already been added. Key in dictionary: '1' Key being added: '1'
hsh.Add("1", "1");
hsh.Add("2", "1");
hsh.Add("3", "1");
hsh.Add("4", "1");
hsh.Add("5", "1");
I tried putting code as follows:
hsh.Add(KV("Table:", rowDatabase["table_name"].
Business Accounts
Answer for Membership
by: burakiewiczPosted on 2009-10-12 at 09:51:56ID: 25552810
does your querystring have all of the same values in it when you redirect looks like the links only provide 1 value like tablename or db, but the code is looking for both to be present. which line does it bomb on?