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How to Set Enable False All textbox available on panel control
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See more: C#4.0.NET4
Here is my code...this code generate Error....so help me.
 
public void ShowHideControl(Control control)
        {
            TextBox tb = control as TextBox;
            tb.Enabled = false;
            ComboBox cb = control as ComboBox;
            cb.Enabled = false;
            if (control.HasChildren)
            {
                foreach (Control child in control.Controls)
                {
                    ClearControl(child);
                }
            }
        }
 

Error message is "nullreferenceexception was unhandled " and "Object reference not set to an instance of an object."
Posted 26 Dec '12 - 20:08
Shambhoo kumar2.7K
Edited 26 Dec '12 - 20:16
Sushil Mate6.2K
v2
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Comments
Sergey Alexandrovich Kryukov - 27 Dec '12 - 2:10
In what line? —SA
Sergey Alexandrovich Kryukov - 27 Dec '12 - 2:14
I see. And what, you did not use the debugger? Please, always execute the code under debugger and learn what happens before asking such questions. This kind of exception is the easiest one to detect and fix. —SA
Shambhoo kumar - 27 Dec '12 - 6:55
tb.Enabled = false;

2 solutions

i solve my self by another process.....
 
 TextBox[] Txtarr=new TextBox[]{txtcustname,txtbilladd,txtshipadd,txtEmail,txtphone,txtMobile,txtFax,txtState,TxtCity};
public void ShowHideControl(TextBox[] tbArray,int x)
       {
           for (int i = 0; i < tbArray.Length; i++)
           {
               if (x == 0)
               {
                   tbArray[i].Enabled = false;
               }
               else
               {
                   tbArray[i].Enabled = true;
               }
           }
       }
  Permalink  
Posted 28 Dec '12 - 1:51
Shambhoo kumar2.7K
The operator as is a dynamic type cast: a type check and the cast at the same time. If the object is not of the checked type, it returns null. You should check the result for null and not use it (not dereference) if it is null.
 
It will solve the problem.
 
[EDIT]
 
Also, you code lacks recursion; in general case, the controls in question could be placed in some child controls as panels. Your could should not depend on that, so the recursive check of all controls is important.
 
—SA
  Permalink  
Posted 26 Dec '12 - 20:12
Sergey Alexandrovich Kryukov586K
Edited 26 Dec '12 - 20:16
v2
Add a Solution

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