How to convert javascript object to json : I am trying to convert the follwing javascript object into valid json-

    [{ 
     '"Sno"': '"1"',
     '"Purchase Date Time"': '"2017-11-14 14:09:32"',
     '"Txn Type"': '"COD"',
     '"Order Status"': '"DELIVERED"'
    },
     { 
     '"Sno"': '"2"',
     '"Purchase Date Time"': '"2017-11-14 14:09:32"',
     '"Txn Type"': '"COD"',
     '"Order Status"': '"DELIVERED"'
    }]

How can I do that?