Brief analysis of readonly and enabled property of js setting control

How do I set the readonly and enabled properties of a control with js?  

I've tried this no,text1 is < Input type = text  Id = text1 >    

Text1. Readonly = true;    
     
And    

Text1. Enabled = true;    

No, why??    

The answer:

Disabled = flase;         / / lowercase
ReadOnly = true;         / / the capital