Get User.Identity.GetUserId in SQL query

Question

Trying to get currently logged in users userid and use it in an SQL query from behindcode to fill a gridview but its not working any ideas what I'm doing wrong. I keep getting a null value error. Also I'm trying to only use the Microsoft.AspNet.Identity if thats even possible

pageload

if (!IsPostBack)
    {
        SqlDataSource SqlDataSource1 = new SqlDataSource();
        SqlDataSource1.ID = "SqlDataSource1";
        this.Page.Controls.Add(SqlDataSource1);
        SqlDataSource1.InsertParameters["luser"].DefaultValue = User.Identity.GetUserId();
        SqlDataSource1.ConnectionString = System.Configuration.ConfigurationManager.ConnectionStrings["DefaultConnection"].ConnectionString;
        SqlDataSource1.SelectCommand = "SELECT top 3 UserId, Friending from Friendreq Where Friending = @luser";
        GridView1.DataSource = SqlDataSource1;
        GridView1.DataBind();
    }

UPDATE:

I was able to get the results that i wanted by adding the requested directly into the SQL query. Is there any reason that i should not add it that what

 SqlDataSource SqlDataSource1 = new SqlDataSource();
    SqlDataSource1.ID = "SqlDataSource1";
    this.Page.Controls.Add(SqlDataSource1);

    SqlDataSource1.ConnectionString = System.Configuration.ConfigurationManager.ConnectionStrings["DefaultConnection"].ConnectionString;
    SqlDataSource1.SelectCommand = "SELECT top 3 UserId, Friending from Friendreq Where Friending = '"+User.Identity.GetUserId()+"'";
    GridView1.DataSource = SqlDataSource1;
    GridView1.DataBind();

Solution = Friending = '"+User.Identity.GetUserId()+"'";

Which line throws an error? Also see [What is a NullReferenceException and how do I fix it?](http://stackoverflow.com/q/4660142/728795) — Andrei, Nov 19 '15 at 14:58
@Andrei i get the error on the **SqlDataSource1.InsertParameters["luser"].DefaultValue = User.Identity.GetUserId();** line and the error is " An exception of type 'System.NullReferenceException' occurred in App_Web_3lu2kaoo.dll but was not handled in user code" — user3266908, Nov 19 '15 at 15:08

Avinash Jain · Answer 1 · 2015-11-19T19:52:41.827

1

If are trying to get user identity from HttpContext then try following code instead. Identity store username/id (based on your logic) in Name property.

Also the object reference error is coming because you have not added "luser" in InsertParameter, but trying to set default value for it. I have added this SqlDataSource1.InsertParameters.Add(new Parameter("luser")); to make sure it have the parameter, before you use it

if (!IsPostBack)
    {
        SqlDataSource SqlDataSource1 = new SqlDataSource();
        SqlDataSource1.ID = "SqlDataSource1";
        this.Page.Controls.Add(SqlDataSource1);
        SqlDataSource1.InsertParameters.Add(new Parameter("luser"));
        SqlDataSource1.InsertParameters["luser"].DefaultValue = HttpContext.Current.User.Identity.IsAuthenticated ? HttpContext.Current.User.Identity.Name : String.Empty;
        SqlDataSource1.ConnectionString = System.Configuration.ConfigurationManager.ConnectionStrings["DefaultConnection"].ConnectionString;
        SqlDataSource1.SelectCommand = "SELECT top 3 UserId, Friending from Friendreq Where Friending = @luser";
        GridView1.DataSource = SqlDataSource1;
        GridView1.DataBind();
    }

edited Nov 19 '15 at 19:52

answered Nov 19 '15 at 15:16

Avinash Jain

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im still getting the same error. Also im using this code as the pageload. so im thinking that maybe that has something to do with the issue. Im new to coding so im not sure. – user3266908 Nov 19 '15 at 15:32
What type of authentication you are using? – Avinash Jain Nov 19 '15 at 17:25
Forms authentication (Microsoft.AspNet.Identity) – user3266908 Nov 19 '15 at 19:16
I got the issue. It is not with User.Identity, but you are getting null reference because SqlDataSource1.InsertParameters["luser"] is null and .DefaultValue after this will throw object reference error – Avinash Jain Nov 19 '15 at 19:46
I have updated the code to add the parameter before you use it – Avinash Jain Nov 19 '15 at 19:49
I tried the changes but now im getting a error stating that i must declare a value for luser. – user3266908 Nov 20 '15 at 14:01
thanks to your help i was able to figure out another way of doing it. I included it in my update. is there any issues doing it this way – user3266908 Nov 20 '15 at 16:17

Get User.Identity.GetUserId in SQL query

1 Answers1