?
Solved

The variable 'sql' is assigned but its value is never used

Posted on 2009-05-13
3
Medium Priority
?
733 Views
Last Modified: 2013-12-17
Good afternoon expert,

Getting error messages in VS 2005
The variable 'sql' is assigned but its value is never used
The variable 'connStringl' is assigned but its value is never used

But they are used at
dsToolkit.SelectCommand = sql;
and
dsToolkit.ConnectionString = connString;

So why does th compiler complain?

Allen



using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
 
public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        //Default SQL statement which will be executed when no search conditions were entered
        String sql = "SELECT tblSecurity.Username, tblSecurity.First_Name, tblSecurity.Last_Name, tblSecurity.Company_number FROM tblSecurity";
        //Connection string - @@DBName will be replaced by the server name selected from the
        //Environment dropdown
        String connString = "DATA SOURCE = Labsdirvg600;Initial Catalog=TimeEntry;User ID=Labswirvg600;Password=Kling0n1";
        //A boolean field which is used to add a WHERE clause to the SQL statement
        //Boolean whereClauseAdded = false;
 
        //Connection string is formed here. cboEnvironment.SelectedItem.Value will return
        //the selected environment.
        //connString = connString.Replace("@@DBName", cboEnvironment.SelectedItem.Value);
    }
 
    protected void btnSubmit_Click(object sender, EventArgs e)
    {
        if (query.Checked)
            sql = "SELECT * from tblSecurity where Username Like '%sm'";
        if (query.Checked)
 
            sql = "SELECT * from tblSecurity where Username Like '%jo'";
 
 
        //Set the connection string of the SQLDataSource here
        dsToolkit.ConnectionString = connString;
 
        //Atleast one search criteria must be entered by the user if a WHERE clause needs to be
        //added
 
        //Now, the dynamically created SQL statement needs to be assigned to the SQL Data source
        dsToolkit.SelectCommand = sql;
 
        //Finally, refresh the Grid, which will cause the data source to execute the above created
        //SQL and show the results in the grid
        grdPayroll.DataBind();
    }
 
}

Open in new window

0
Comment
Question by:Allen Pitts
  • 2
3 Comments
 
LVL 143

Expert Comment

by:Guy Hengel [angelIII / a3]
ID: 24379389
change:
 protected void btnSubmit_Click(object sender, EventArgs e)
    {
        sql = string.empty;
        if (query.Checked)
            sql = "SELECT * from tblSecurity where Username Like '%sm'";
        if (query.Checked)
 
            sql = "SELECT * from tblSecurity where Username Like '%jo'";
 

Open in new window

0
 

Author Comment

by:Allen Pitts
ID: 24379526
Angelll,

Installed code now get
Warning      2      The variable 'sql' is assigned but its value is never used      C:\Inetpub\wwwroot\TK090514\Default.aspx.cs      16      16      C:\...\TK090514\
Warning      3      The variable 'connString' is assigned but its value is never used      C:\Inetpub\wwwroot\TK090514\Default.aspx.cs      19      16      C:\...\TK090514\
Error      4      The name 'sql' does not exist in the current context      C:\Inetpub\wwwroot\TK090514\Default.aspx.cs      31      9      C:\...\TK090514\
Error      5      'string' does not contain a definition for 'empty'      C:\Inetpub\wwwroot\TK090514\Default.aspx.cs      31      22      C:\...\TK090514\
Error      6      The name 'query' does not exist in the current context      C:\Inetpub\wwwroot\TK090514\Default.aspx.cs      32      13      C:\...\TK090514\
Error      7      The name 'sql' does not exist in the current context      C:\Inetpub\wwwroot\TK090514\Default.aspx.cs      33      13      C:\...\TK090514\
Error      8      The name 'query' does not exist in the current context      C:\Inetpub\wwwroot\TK090514\Default.aspx.cs      34      13      C:\...\TK090514\
Error      9      The name 'sql' does not exist in the current context      C:\Inetpub\wwwroot\TK090514\Default.aspx.cs      36      13      C:\...\TK090514\
Error      10      The name 'connString' does not exist in the current context      C:\Inetpub\wwwroot\TK090514\Default.aspx.cs      42      38      C:\...\TK090514\
Error      11      The name 'sql' does not exist in the current context      C:\Inetpub\wwwroot\TK090514\Default.aspx.cs      52      35      C:\...\TK090514\
0
 
LVL 143

Accepted Solution

by:
Guy Hengel [angelIII / a3] earned 2000 total points
ID: 24379560
sorry, I got the error message wrong.

the problem is that you define sql in the page load, instead of the class level
using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
 
public partial class _Default : System.Web.UI.Page
{
    String sql = String.Empty; 
 
    protected void Page_Load(object sender, EventArgs e)
    {
        //Default SQL statement which will be executed when no search conditions were entered
        sql = "SELECT tblSecurity.Username, tblSecurity.First_Name, tblSecurity.Last_Name, tblSecurity.Company_number FROM tblSecurity";
        //Connection string - @@DBName will be replaced by the server name selected from the
        //Environment dropdown
        String connString = "DATA SOURCE = Labsdirvg600;Initial Catalog=TimeEntry;User ID=Labswirvg600;Password=Kling0n1";
        //A boolean field which is used to add a WHERE clause to the SQL statement
        //Boolean whereClauseAdded = false;
 
        //Connection string is formed here. cboEnvironment.SelectedItem.Value will return
        //the selected environment.
        //connString = connString.Replace("@@DBName", cboEnvironment.SelectedItem.Value);
    }
 
    protected void btnSubmit_Click(object sender, EventArgs e)
    {
        if (query.Checked)
            sql = "SELECT * from tblSecurity where Username Like '%sm'";
        if (query.Checked)
 
            sql = "SELECT * from tblSecurity where Username Like '%jo'";
 
 
        //Set the connection string of the SQLDataSource here
        dsToolkit.ConnectionString = connString;
 
        //Atleast one search criteria must be entered by the user if a WHERE clause needs to be
        //added
 
        //Now, the dynamically created SQL statement needs to be assigned to the SQL Data source
        dsToolkit.SelectCommand = sql;
 
        //Finally, refresh the Grid, which will cause the data source to execute the above created
        //SQL and show the results in the grid
        grdPayroll.DataBind();
    }
 
}

Open in new window

0

Featured Post

VIDEO: THE CONCERTO CLOUD FOR HEALTHCARE

Modern healthcare requires a modern cloud. View this brief video to understand how the Concerto Cloud for Healthcare can help your organization.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

This article describes relatively difficult and non-obvious issues that are likely to arise when creating COM class in Visual Studio and deploying it by professional MSI-authoring tools. It is assumed that the reader is already familiar with the cla…
Simulator games are perfect for generating sample realistic data streams, especially for learning data analysis. It is even useful for demoing offerings such as Azure stream analytics, PowerBI etc.
The viewer will learn how to use NetBeans IDE 8.0 for Windows to connect to a MySQL database. Open Services Panel: Create a new connection using New Connection Wizard: Create a test database called eetutorial: Create a new test tabel called ee…
THe viewer will learn how to use NetBeans IDE 8.0 for Windows to perform CRUD operations on a MySql database.
Suggested Courses
Course of the Month14 days, 15 hours left to enroll

840 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question