An event method is just another method. Call it as you would any other method.
If you don't use the parameters in your code then you can use null place holder.
E.G cbPW_TextChanged(null, null); If you use the sender or event arg parameters then you must supply appropriate objects so your code will work.
E.G. cbPW_TextChanged(cbPW, new EventArgs());
To attach and detach a method you use the += and -= operators.
// attach handler
cbPW.TextChanged += new EventHandler(cbPW_TextChanged);
// detach handler
cbPW.TextChanged -= new EventHandler(cbPW_TextChanged);
To find out what the handler syntax is, add the event handler in the normal way and then right click on the method name and select Find All References. One of them will be a reference to the designer code and use the += operator to attach your method.