C# Does performance degrade if I use a large ViewState names?

Question

I personally like option one below for maintainability but I could see option two getting me better performance. Option three is probably complete garbage.

1. ViewState["Calendar1.SelectionMode"] = Calendar1.SelectionMode;
2. ViewState["CSM"] = Calendar1.SelectionMode;
3. ViewState["Calendar1_SelectionMode"] = Calendar1.SelectionMode;

Am I applying old school habits of thinking about the maintenance? Does it matter only when the number of objects is large? I cannot see the internals using anything but a very efficient hash. I have read up on methods to speed up the page loading but nothing directly advising as this being even a slight factor. All the literature talks about is prefering the viewstate over database access reads, using compact types, populating only those values that take on non default values.

Answer 1

Option two will probably give you better performance, but the difference is extremely small. If you're experiencing performance problems this would be one of the very last places I would look for bottlenecks. Have you run any kind of profiling on your page? That's where I would start looking.

Answer 2

The key names become part of the viewstate hidden field. Crude example:

protected void Page_Load(object sender, EventArgs e)
{
    // ViewState["a"] = 1;
    // <input type="hidden" name="__VIEWSTATE" id="__VIEWSTATE"   
    // value="/wEPDwUJNzgzNDMwNTMzDxYCHgFhAgFkZCdtAzza2+uuoGpYdGLBUdCkUGe7" />

    // ViewState["this is a very very very very long key"] = 1;
    // <input type="hidden" name="__VIEWSTATE" id="__VIEWSTATE" 
    // value="/wEPDwUJNzgzNDMwNTMzDxYCHiZ0aGlzIGlzIGEgdmVyeSB2ZXJ5IHZlcnkgdmVyeSBsb25nIGtleQIBZGSmj9cou408+XXRLxCLKcEoLngriA==" />

}

Bottom line: unless you are storing a large number of keys, likely not an issue.