Cannot implicitly convert type 'string' to 'System.DateTime'

Hi,

I have a DateTime field in my sql server database. The field can take null value.

In my aspx page, i have a textbox to get the input from the user. If the textbox value is empty, how to handle it?

This is my cs code: objMyTime.StartTime = DateTime.Parse(txtStartTime.Text);
  I am getting error as: "Cannot implicitly convert type 'string' to 'System.DateTime' "

Thank you
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