How to solve Object reference not set to an instance of an object.?

c# asp.net nullreferenceexception
r.vengadesh picture r.vengadesh · Nov 22, 2013 · Viewed 530.3k times · Source

In my asp.net program.I set one protected list.And i add a value in list.But it shows Object reference not set to an instance of an object error

protected List<string> list;
protected void Page_Load(object sender, EventArgs e)
{
     list.Add("hai");
}

How to solve this error?

Answer

Tinsa picture Tinsa · Nov 22, 2013

You need to initialize the list first:

protected List<string> list = new List<string>();

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