title: Operator '==' cannot be applied to operands of type 'char' and 'string'
body: <p>I have a registration application which has the "KeyChar" event inside it, and it works great ! but when i give the same lines of code in this application it gives me <code>Operator '=='/'!=' cannot be applied to operands of type 'char' and 'string'</code></p>
  
  <p>Can't seem to figure out why it works in the other application but not here!
  Any help is much appreciated !</p>
  
  <pre><code> private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
      {
          SqlConnection DBConnection = new SqlConnection("Data Source=DATABASE;Initial Catalog=imis;Integrated Security=True");
          SqlCommand cmd = new SqlCommand();
  
          Object returnValue;
  
          string txtend = textBox1.Text;
          //string lastChar = txtend.Substring(txtend.Length - 1);
  
          if (e.KeyChar == "L")
          {
              DBConnection.Open();
          }
          if (DBConnection.State == ConnectionState.Open)
          {
              if (textBox1.Text.Length != 7) return;
              {
                  //cmd.CommandText = ("SELECT last_name +', '+ first_name +'\t ('+major_key+')\t' from name where id =@Name");
                  cmd.CommandText = ("SELECT last_name +', '+ first_name from name where id =@Name");
                  cmd.Parameters.Add(new SqlParameter("Name", textBox1.Text.Replace(@"L", "")));
                  cmd.CommandType = CommandType.Text;
                  cmd.Connection = DBConnection;
                  // sqlConnection1.Open();
                  returnValue = cmd.ExecuteScalar() + "\t (" + textBox1.Text.Replace(@"L", "") + ")";
                  DBConnection.Close();
  
                  if (listBox1.Items.Contains(returnValue))
                  {
                      for (int n = listBox1.Items.Count - 1; n &gt;= 0; --n)
                      {
                          string removelistitem = returnValue.ToString();
                          if (listBox1.Items[n].ToString().Contains(removelistitem))
                          {
                              listBox1.Items.RemoveAt(n);
                              //listBox1.Items.Add(removelistitem+"    " +TimeOut+ Time);
                          }
  
                      }
                  }
                  else
                      listBox1.Items.Add(returnValue);
  
                  System.IO.StreamWriter SaveFile = new System.IO.StreamWriter(fullFileName);
                  foreach (object item in listBox1.Items)
                      SaveFile.WriteLine(item.ToString());
                  SaveFile.Flush();
                  SaveFile.Close();
  
                  textBox1.Clear();
  
                  if (listBox1.Items.Count != 0) { DisableCloseButton(); }
                  else
                  {
                      EnableCloseButton();
                  }
                  Current_Attendance_Label.Text = "Currently " + listBox1.Items.Count.ToString() + " in attendance.";
                  e.Handled = true;
              }
          }
          /////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
          else
          //////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
          {
              returnValue = textBox1.Text.Replace(@"*", "");
  
              if (e.KeyChar == "*") return;
              {
                  if (listBox1.Items.Contains(returnValue))
                  {
                      for (int n = listBox1.Items.Count - 1; n &gt;= 0; --n)
                      {
                          string removelistitem = returnValue.ToString();
                          if (listBox1.Items[n].ToString().Contains(removelistitem))
                          {
                              //listBox1.Items.RemoveAt(n);
                          }
                      }
                  }
                  else
                      listBox1.Items.Add(returnValue);
                  textBox1.Clear();
                  System.IO.StreamWriter SaveFile = new System.IO.StreamWriter(fullFileName);
                  foreach (object item in listBox1.Items)
                      SaveFile.WriteLine(item.ToString());
                  SaveFile.Flush();
                  SaveFile.Close();
                  if (listBox1.Items.Count != 0) { DisableCloseButton(); }
                  else
                  {
                      EnableCloseButton();
                  }
                  Current_Attendance_Label.Text = "Currently " + listBox1.Items.Count.ToString() + " in attendance.";
                  e.Handled = true;
              }
          }
      }
  </code></pre>