Question

i have one dataset with 3 data tables again i have to add one more data table in same dataset at first position(Ex:mydataset.tables[0]th position) .can any one help me regarding this.

Answer 1

You will probably need to pull all the datatables out of the dataset into a list, get them in the right order, and then re-add them all to the dataset since you cannot insert to or modify the existing order:

var tables = new DataTable[4];
tables[0] = mynewtable;
tables[1] = mydataset.Tables[0];
tables[2] = mydataset.Tables[1];
tables[3] = mydataset.Tables[2];
mydataset.Tables.Clear();
mydataset.Tables.Add(Tables[0]);
mydataset.Tables.Add(Tables[1]);
mydataset.Tables.Add(Tables[2]);
mydataset.Tables.Add(Tables[3]);