contact1 : {name: "Kesh", relation: "Mother", number: "9819269972"}

var obj, dbParam, xmlhttp, myObj, x, txt = "";
obj = { "table":"Successful", "limit":20 };
dbParam = JSON.stringify(obj);
xmlhttp = new XMLHttpRequest();
xmlhttp.onreadystatechange = function() {
   if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
        myObj = JSON.parse(xmlhttp.responseText);
        var contact1 = myObj.contact1;
    console.log(contact1);
    console.log(contact1.name);
}