convert date from json format to other formats in sencha

Can anyone tell me how to convert date from Json data to normal date format in sencha.

var df = this.dateFormat;
 
 if (!v) {
     return v;
 }
 if (Ext.isDate(v)) {
     return v;
 }
 if (df) {
     if (df == 'timestamp') {
         return new Date(v * 1000);
     }
     if (df == 'time') {
         return new Date(parseInt(v, 10));
     }
     return Date.parseDate(v, df);
 }
 var parsed = Date.parse(v);
 return parsed ? new Date(parsed) : null;
 

Thanks in advance

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