Question about try/catch for null variables

[raylopez99]

Is there a better way (faster, cleaner) of checking for a null than
the below? I tried various other ways (commented out) and they give
run-time errors.

treeView1.Node[999] does not exist, it's a null.

TX

RL

try
{
if (treeView1.Nodes[999] == null)
throw new ArgumentException("Node cannot be
null!");
}

//if ((this.treeView1.Nodes[999] == null)) //doesn't work,
compiles but run time error
//{
// TreeNode bogusTreeNode = treeView1.Nodes[999];
// MessageBox.Show("bogus node!!");
//}
//next line will will trigger exception "out of bounds",
run-time
//if (!(bogusTreeNode.Parent != null))
{ MessageBox.Show("bogus node!"); }

catch (ArgumentException ex)
{
// MessageBox.Show("exception! bogus node"); //works
}

[Ignacio Machin ( .NET/ C# MVP )]

On Jul 25, 1:45*pm, raylopez99 <[e-mail]:

Is there a better way (faster, cleaner) of checking for a null than
the below? *I tried various other ways (commented out) and they give
run-time errors.

treeView1.Node[999] does not exist, it's a null.

TX

RL

* * * * * * try
* * * * * * {
* * * * * * * * if (treeView1.Nodes[999] == null)
* * * * * * * * * * throw new ArgumentException("Nodecannot be
null!");
* * * * * * }

* * * * * * //if ((this.treeView1.Nodes[999] == null)) //doesn't work,
compiles but run time error
* * * * * * //{
* * * * * * // * *TreeNode bogusTreeNode = treeView1.Nodes[999];
* * * * * * // * *MessageBox.Show("bogus node!!");
* * * * * * //}
* * * * * * //next line will will trigger exception "out of bounds",
run-time
* * * * * * //if (!(bogusTreeNode.Parent *!= null))
{ MessageBox.Show("bogus node!"); }

* * * * * * catch (ArgumentException ex)
* * * * * * {
* * * * * * * // *MessageBox.Show("exception! bogus node"); //works
* * * * * * }

what about treeView.Nodes.Count < 999

[raylopez99]

On Jul 25, 12:09*pm, "Ignacio Machin ( .NET/ C# MVP )"
<[e-mail]:

On Jul 25, 1:45*pm, raylopez99 <[e-mail]:

Is there a better way (faster, cleaner) of checking for a null than
the below? *I tried various other ways (commented out) and they give
run-time errors.

treeView1.Node[999] does not exist, it's a null.

* * * * * * }

what about treeView.Nodes.Count < 999

Good one, that makes sense!

Tx

RL