Behavior of "cross threaded operation not valid"
===

I was trying to read in values from the GUI and i passed the data as show below using task.What i don't understand is it gives error because of only combobox feild (that is tab3_ddl_Range.SelectedText) and if i remove it the error goes away, Shouldn't it still give the error ?, as i am accessing GUI form non GUI thread?.

        factoryA.StartNew(() => ReadInstrument_3(Globls.numReadings, tab3_txt_Address.Text.TrimEnd(), tab3_rb_DCI.Checked, tab2_rb_DCV.Checked, tab3_ddl_Range.SelectedText.TrimEnd(), tab3_rb_FixedZ_10G.Checked, tab3_rb_FixedZ_10M.Checked, tab3_rb_Azero_Off.Checked, tab3_rb_Azero_On.Checked, tab3_rb_Azero_Once.Checked, tab3_txt_Aper.Text.TrimEnd(), tab3_txt_Device_Timeout.Text.TrimEnd(), tab3_txt_SICL.Text.TrimEnd())