How to get checked status of checkbox on Crm 4.0?

I开发者_StackOverflow中文版 have 2 checkboxes on myform how can i know checked or not this items in onload()

The value (checked or not) of a boolean field is stored in the DataValue property.

var isChecked = crmForm.all.SOME_BOOLEAN_FIELD_ID.DataValue;

See http://msdn.microsoft.com/en-us/library/cc189798.aspx