再建一个datatable，然后把原来的datatable赋值过来，就可以了code:---------原来的datatable：dt---------DataTabledt=newDataTable("test");DataColumndc=newDataColumn();dc=dt.Columns.Add("a",typeof(string));dc=dt.Columns.Add("b",typeof(string));DataRowdr;dr=dt.NewRow();dr["a"]="you";dr["b"]="welcome";dt.Rows.Add(dr);dr=dt.NewRow();dr["a"]="me";dr["b"]="hello";dt.Rows.Add(dr);---------------新建datatable:dt1---------------DataTabledt1=newDataTable("test1");dc=dt1.Columns.Add("c",typeof(Int32));dc.AutoIncrement=true;dc.AutoIncrementSeed=1;dc.AutoIncrementStep=1;dc=dt1.Columns.Add("a",typeof(string));dc=dt1.Columns.Add("b",typeof(string));inti=0;foreach(DataRowdr1indt.Rows){dt1.Rows.Add(dt1.NewRow());dt1.Rows[i]["a"]=dr1["a"].ToString();dt1.Rows[i]["b"]=dr1["b"];i++;}