[рони]

mazahaler,

var data = [{
    "ID": "8",
    "MainID_Ref": "3510",
    "ParentType": "60",
    "ObjectType": "117",
    "String1": null,
    "String2": "222",
    "String3": null,
    "String4": null,
    "String5": null,
    "String6": null,
    "String7": "222",
    "String8": null,
    "String9": null,
    "String10": null,
    "LongInt1": null,
    "Double1": null,
    "Double2": null,
    "Memo1": null,
    "Memo2": null
}]
alert(data[0].String2);