i need sample code for using updateCriterion() function of CriterionServiceService... here is my C# code:

Criterion[] newkeywordlist = new Keyword[1]; newkeywordlist[0] = new Keyword();

/*i have tried Criterion[] newkeywordlist = new Criterion[1]; newkeywordlist[0] = new Criterion();

but Criterion is a abtract class so variable cannot be created */ newkeywordlist[0].criterionType = "Keyword"; newkeywordlist[0].id= myCriterionStats[0].id; newkeywordlist[0].adGroupId = groupList[1].id; newkeywordlist[0].maxCpc=2000000; \\ error here max does exist in Criterion newkeywordlist[0].maxCpcSpecified = true; \\ error here maxCpcSpecified does exist in Criterion newkeywordlist[0].negative = false;

criterion.updateCriteria(newkeywordlist);\\error here Invalid cast

help me out