title: System.FormatException when Converting a Value
body: <p>I am receving the error </p>
  
  <blockquote>
    <p><code>System.FormatException</code></p>
  </blockquote>
  
  <p>when I click on <code>Button1</code> after entering a persons details</p>
  
  <pre><code>public partial class _Default : Page
  {    
      protected void Button1_Click(object sender, EventArgs e)
      {
          Response.Write("You have successfully added a Person!");    
          Person p = new Person(TextBox1.Text, Convert.ToInt32(TextBox2.Text), 
          TextBox3.Text, TextBox4.Text, Convert.ToBoolean(DropDownList1.SelectedValue), TextBox5.Text);    
          Label1.Text = (p.PresentPerson());
      }
  }
  </code></pre>
  
  <p>Person class:</p>
  
  <pre><code>class Person
  {
      public int Age { get { return Age; } set { Age = value; } }
      public string Name { get { return Name; } set { Name = value; } }
      public string DOB { get { return DOB; } set { DOB = value; } }
      public string TelNo { get { return TelNo; } set { TelNo = value; } }
      public bool Gender { get { return Gender; } set { Gender = value; } }
      public string Address { get { return Address; } set { Address = value; } }
      public string enterPerson;
  
      public Person(string name, int age, string dob, string telNo, bool gender, string address)
      {
          Name = name;
          Age = age;
          DOB = dob;
          TelNo = telNo;
          Gender = gender;
          Address = address;
      }
  
      public string PresentPerson()
      {
          return enterPerson = "Name: " + Name + "\n" + "Age: " + Age + "\n" +  "Date of Birth: "
          + DOB + "\n" + "Telephone Number: " + TelNo + "\n" + "Gender: " + "\n" + "Address: "
          + Address;
      }
  }
  </code></pre>