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POCall to methods results in "Message: Object reference not set to an instance of an object."
 

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  1. POCall to methods results in "Message: Object reference not set to an instance of an object."
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    <p>I cannot figure out why I any of these methods (load_qc_form(); enable_qc_form();disable_qc_form();) I get the "Message: Object reference not set to an instance of an object." message.</p> <p>How can calling a method return null??</p> <p>Here is my entire code. I am new to C# and am trying to update an existing page. Could someone point me in the right direction? </p> <p>I want to be able to call these methods from anywhere in the application. </p> <pre><code> namespace test_page { using System; //using System.Windows.Forms; using System.Data; using System.Drawing; using System.Web; using System.Web.UI.WebControls; using System.Web.UI.HtmlControls; using System.Data.SqlClient; /// &lt;summary&gt; /// Summary description for ProductionQC. /// &lt;/summary&gt; /// public class hendrix : System.Web.UI.UserControl { #region class_variable_declarations //Test Boxes protected System.Web.UI.WebControls.TextBox boxOrder; protected System.Web.UI.WebControls.TextBox boxBox; protected System.Web.UI.WebControls.TextBox boxPallet; protected System.Web.UI.WebControls.TextBox boxPulpTemp; protected System.Web.UI.WebControls.TextBox boxComments; protected System.Web.UI.WebControls.TextBox boxMajdef1; protected System.Web.UI.WebControls.TextBox boxMajdef2; protected System.Web.UI.WebControls.TextBox boxMajdef3; protected System.Web.UI.WebControls.TextBox boxMindef1; protected System.Web.UI.WebControls.TextBox boxMindef2; protected System.Web.UI.WebControls.TextBox boxMindef3; protected System.Web.UI.WebControls.TextBox boxSamples; //drop down lists protected System.Web.UI.WebControls.DropDownList listYN; protected System.Web.UI.WebControls.DropDownList listMaj1; protected System.Web.UI.WebControls.DropDownList listMaj2; protected System.Web.UI.WebControls.DropDownList listMaj3; protected System.Web.UI.WebControls.DropDownList listMin1; protected System.Web.UI.WebControls.DropDownList listMin2; protected System.Web.UI.WebControls.DropDownList listMin3; protected System.Web.UI.WebControls.DropDownList listRecorder; //labels protected System.Web.UI.WebControls.Label lblPalletTag; protected System.Web.UI.WebControls.Label lblmajdef1; protected System.Web.UI.WebControls.Label lblmajdef2; protected System.Web.UI.WebControls.Label lblmajdef3; protected System.Web.UI.WebControls.Label lblmindef1; protected System.Web.UI.WebControls.Label lblmindef2; protected System.Web.UI.WebControls.Label lblmindef3; protected System.Web.UI.WebControls.Label lblPulpTemp; protected System.Web.UI.WebControls.Label lblComments; protected System.Web.UI.WebControls.Label lblPackageCorrect; protected System.Web.UI.WebControls.Label lblTotSamples; protected System.Web.UI.WebControls.Label lblrecorder; //Buttons protected System.Web.UI.WebControls.Button btnGo; protected System.Web.UI.WebControls.Button btnGo2; protected System.Web.UI.WebControls.Button btnGo3; protected System.Web.UI.WebControls.Button btnClear; //Gridviews protected System.Web.UI.WebControls.GridView grdDisplayOrd; protected System.Web.UI.WebControls.GridView grdDisplayBox; //Data connections - adapters protected System.Data.SqlClient.SqlCommand cmdData; protected System.Data.SqlClient.SqlConnection sqlConnection1; protected System.Data.SqlClient.SqlDataReader dataReader; #endregion class_variable_declarations private void Page_Load(object sender, System.EventArgs e) { //initializePage(); // Put user code to initialize the page here if (!this.Page.IsPostBack) { //load_qc_form(); //disable_qc_form(); } } //private void initializePage() // { // throw new NotImplementedException(); //} #region Web Form Designer generated code override protected void OnInit(EventArgs e) { // // CODEGEN: This call is required by the ASP.NET Web Form Designer. // InitializeComponent(); base.OnInit(e); } /// &lt;summary&gt; /// Required method for Designer support - do not modify /// the contents of this method with the code editor. /// &lt;/summary&gt; private void InitializeComponent() { this.sqlConnection1 = new System.Data.SqlClient.SqlConnection(); this.btnGo.Click += new System.EventHandler(this.btnGo_Click); this.btnGo2.Click += new System.EventHandler(this.btnGo2_Click); // this.btnGo3.Click += new System.EventHandler(this.btnGo3_Click); this.btnClear.Click += new EventHandler(this.btnClear_Click); // // sqlConnection1 // this.sqlConnection1.ConnectionString = "workstation id=\"******";packet size=4096;user id=******;data source=\"******";persis" + "t security info=True;initial catalog=****;password=**********"; this.Load += new System.EventHandler(this.Page_Load); } #endregion // public virtual string DisplayMember { get; set; } //get and display order data private void btnGo_Click(object sender, System.EventArgs e) { { SqlCommand cmd = new SqlCommand(); cmd.CommandText = "Select ord.order_number as Order#,var.description as Description,grd.description as Grade, " + "size.description as Size,pkg.description as Pkg, ord.container_type as Pallet " + "FROM t_item_master itm INNER JOIN t_order_detail ord (NOLOCK) ON ord.item_number = itm.item_number " + "LEFT OUTER JOIN t_package pkg (NOLOCK) ON pkg.package_name = itm.product_package_code " + "LEFT OUTER JOIN t_grade grd (NOLOCK) ON grd.grade_id = itm.grade_id " + "LEFT OUTER JOIN t_size size (NOLOCK) ON size.size_id = itm.size_id AND size.package_id = pkg.package_id " + "LEFT OUTER JOIN t_variety var (NOLOCK) ON var.variety_id = itm.variety_id " + "WHERE order_number like @order_number"; cmd.Parameters.Add("@order_number", SqlDbType.VarChar).Value = boxOrder.Text; cmd.CommandType = CommandType.Text; cmd.Connection = this.sqlConnection1; this.sqlConnection1.Open(); this.grdDisplayOrd.Visible = true; SqlDataAdapter adpt = new SqlDataAdapter(cmd); DataSet ds = new DataSet(); adpt.Fill(ds); grdDisplayOrd.DataSource = ds; grdDisplayOrd.DataBind(); this.sqlConnection1.Close(); } } // get and display box data private void btnGo2_Click(object sender, System.EventArgs e) { { load_qc_form(); SqlCommand cmd = new SqlCommand(); HyperLink test_link1 = new HyperLink(); cmd.CommandText = "select " + "item_number as Item#, " + "description as Desctiption, " + "grower_lot as Lot#, " + "pack_date as Packed " + "from v_box_data where box_id = @box_id"; cmd.Parameters.Add("@box_id", SqlDbType.VarChar).Value = boxBox.Text; cmd.CommandType = CommandType.Text; cmd.Connection = this.sqlConnection1; this.sqlConnection1.Open(); this.grdDisplayBox.Visible = true; SqlDataAdapter adpt = new SqlDataAdapter(cmd); DataSet ds = new DataSet(); adpt.Fill(ds); grdDisplayBox.DataSource = ds; grdDisplayBox.DataBind(); this.sqlConnection1.Close(); } } private void load_qc_form() { #region declare_variables // string pallet_tag; //string correct_package; //string total_samples; //string majdef1; //string majdef2; //string majdef3; // string mindef1; // string mindef2; // string mindef3; // string majcnt1; // string majcnt2; //string majcnt3; // string mincnt1; // string mincnt2; // string mincnt3; // string pulptemp; // string comments; string recorder; #endregion declare_variables #region fill_list_recorder try { listRecorder.Items.Clear(); recorder = "select EMPID,FIRSTNAME+' '+LASTNAME from t_famous_employee " + "where COSTCENTERNAME like 'Quality Control - 2011' " + "and HOMECREWID LIKE 'Shipping' "; cmdData = new System.Data.SqlClient.SqlCommand(recorder, this.sqlConnection1); cmdData.Connection = this.sqlConnection1; this.sqlConnection1.Open(); SqlDataAdapter da = new SqlDataAdapter(cmdData); DataTable dt = new DataTable(); da.Fill(dt); listRecorder.DataBind(); listRecorder.DataSource = dt; listRecorder.DataValueField = "EMPID"; listRecorder.DataTextField = "FIRSTNAME+' '+LASTNAME"; this.listRecorder.Items.Insert(0, "FIRSTNAME+' '+LASTNAME"); } catch (Exception) { } this.dataReader.Close(); #endregion } private void btnGo3_Click(object sender, System.EventArgs e) { { } } private void btnClear_Click(object sender, System.EventArgs e) { { this.boxOrder.Text = ""; this.boxBox.Text = ""; this.grdDisplayOrd.Visible = false; this.grdDisplayBox.Visible = false; //disable_qc_form(); } } private void enable_qc_form() { this.listMaj1.Enabled = true; this.listMaj2.Enabled = true; this.listMaj3.Enabled = true; this.listMin1.Enabled = true; this.listMin2.Enabled = true; this.listMin3.Enabled = true; this.listYN.Enabled = true; this.listMaj1.Enabled = true; this.listMaj2.Enabled = true; this.listMaj3.Enabled = true; this.listMin1.Enabled = true; this.listMin2.Enabled = true; this.listMin3.Enabled = true; this.boxComments.Enabled = true; this.boxMajdef1.Enabled = true; this.boxMajdef2.Enabled = true; this.boxMajdef3.Enabled = true; this.boxMindef1.Enabled = true; this.boxMindef2.Enabled = true; this.boxMindef3.Enabled = true; this.boxPallet.Enabled = true; this.boxPulpTemp.Enabled = true; this.boxSamples.Enabled = true; this.lblComments.Enabled = true; this.lblmajdef1.Enabled = true; this.lblmajdef2.Enabled = true; this.lblmajdef3.Enabled = true; this.lblmindef1.Enabled = true; this.lblmindef2.Enabled = true; this.lblmindef3.Enabled = true; this.lblPackageCorrect.Enabled = true; this.lblPalletTag.Enabled = true; this.lblPulpTemp.Enabled = true; this.lblTotSamples.Enabled = true; } private void disable_qc_form() { this.listMaj1.Enabled = false; this.listMaj2.Enabled = false; this.listMaj3.Enabled = false; this.listMin1.Enabled = false; this.listMin2.Enabled = false; this.listMin3.Enabled = false; this.listYN.Enabled = false; this.listMaj1.Enabled = false; this.listMaj2.Enabled = false; this.listMaj3.Enabled = false; this.listMin1.Enabled = false; this.listMin2.Enabled = false; this.listMin3.Enabled = false; this.boxComments.Enabled = false; this.boxMajdef1.Enabled = false; this.boxMajdef2.Enabled = false; this.boxMajdef3.Enabled = false; this.boxMindef1.Enabled = false; this.boxMindef2.Enabled = false; this.boxMindef3.Enabled = false; this.boxPallet.Enabled = false; this.boxPulpTemp.Enabled = false; this.boxSamples.Enabled = false; this.lblComments.Enabled = false; this.lblmajdef1.Enabled = false; this.lblmajdef2.Enabled = false; this.lblmajdef3.Enabled = false; this.lblmindef1.Enabled = false; this.lblmindef2.Enabled = false; this.lblmindef3.Enabled = false; this.lblPackageCorrect.Enabled = false; this.lblPalletTag.Enabled = false; this.lblPulpTemp.Enabled = false; this.lblTotSamples.Enabled = false; } } } </code></pre> <p>So I need to be able to call the method to test my first dropdown list.</p> <p>Thank you in advance for your help!! </p>
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    1. This table or related slice is empty.
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    1. USbriskovich
    1. USbriskovich
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    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
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      1. POCall to methods results in "Message: Object reference not set to an instance of an object."
      1. This table or related slice is empty.
      1. VTDownMod
    1. COPost a short reproducible example, and the exact error and stack trace.
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      1. POCall to methods results in "Message: Object reference not set to an instance of an object."
      1. USasawyer
    2. COAt least add info about which line the exception is occurring on
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      1. POCall to methods results in "Message: Object reference not set to an instance of an object."
      1. USspender
    3. COYou are silently discarding all exceptions...
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      1. POCall to methods results in "Message: Object reference not set to an instance of an object."
      1. USmellamokb
 

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