问题
Joining Values Of Two Columns From DataTable Two columns make it in one columns from datatable
my datatable is
TagNumber, LogNumber Combined
124 1 2
125 1 3
126 2 4
o/p:
TagNumber
124 ~1~2
125 ~1~3
126 ~2~4
combined column is merge from column0 and column1
i dont understand hw can i do please write sample of code
I dont have experience on linq . I add column bt hw can i merge two columns in that one columns
I got answer:
For i As Integer = 0 To dstemp.Tables(0).Rows.Count - 1
dstemp.Tables(0).Rows(i)(0) = dstemp.Tables(0).Rows(i)("TagNumber") & "~" & dstemp.Tables(0).Rows(i)("LogNumber") & "~" & dstemp.Tables(0).Rows(i)("Combined")
next
回答1:
Ok if you really want to do this then you have create a extra DataTable with Three Columns:
TagNumber, LogNumber Combined: as below:
private DataTable CreateDataTableColumns()
{
DataTable dtThreeItems = new DataTable();
dtThreeItems.Columns.Add("TagNumber", typeof(String));
dtThreeItems.Columns.Add("LogNumber", typeof(String));
dtThreeItems.Columns.Add("Combined", typeof(String));
return dtThreeItems;
}
Now iterate the old datatable as below to get combined value:
foreach (DataRow dr in dtTwoItems.Rows)
{
row = dtThreeItems.NewRow();
row["TagNumber"] = dr["TagNumber"].ToString();
row["LogNumber"] = dr["LogNumber"].ToString();
row["Combined"] = dr["TagNumber"].ToString()+"/"+dr["LogNumber"].ToString() ;
dtThreeItems.Rows.Add(row);
}
Thats All
回答2:
Try doing it like this.
dtTwoItems.Columns.Add("Combined", typeof(string), "TagNumber+'/'+LogNumber");
回答3:
DataTable is like a container. It is not proper to join tables.
I recommend you'd use linq.
回答4:
Did you try to Add new Column to DataTable and then iterate through Each Row to put value by combining them?
EDIT: I Am not sure if Linq or Datatable query have some inbuilt feature to do this, but simple solution is what I tell. Or if you are filling your datatable from any SQL Query based database, then write a SQL that has third column with merged value using concat of columns.
Edit2:
foreach (Datarow r in myTable.Rows) {
r["Newcolumn"] = Convert.ToString(r["c1"]) + "/" + Convert.ToString(r["c2"]);
}
来源:https://stackoverflow.com/questions/18140445/joining-values-of-two-columns-from-datatable