How to add New Column with Value to the Existing DataTable?

I have One DataTable with 5 Columns and 10 Rows. Now I want to add one New Column to the DataTable and I want to assign DropDownList value to the New Column. So the DropDownList value should be added 10 times to the New Column. How to do this? Note: Without using FOR LOOP.

For Example: My Existing DataTable is like this.

   ID             Value
-----          -------
1              100
2              150

Now I want to add one New Column "CourseID" to this DataTable. I have One DropDownList. Its selected value is 1. So My Existing Table should be like below:

    ID              Value         CourseID
-----            ------       ----------
1                100             1
2                150             1

How to do this?

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Add the column and update all rows in the DataTable, for example:

DataTable tbl = new DataTable();
tbl.Columns.Add(new DataColumn("ID", typeof(Int32)));
tbl.Columns.Add(new DataColumn("Name", typeof(string)));
for (Int32 i = 1; i <= 10; i++) {
DataRow row = tbl.NewRow();
row["ID"] = i;
row["Name"] = i + ". row";
tbl.Rows.Add(row);
}
DataColumn newCol = new DataColumn("NewColumn", typeof(string));
newCol.AllowDBNull = true;
tbl.Columns.Add(newCol);
foreach (DataRow row in tbl.Rows) {
row["NewColumn"] = "You DropDownList value";
}
//if you don't want to allow null-values'
newCol.AllowDBNull = false;
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最佳答案

Without For loop:

Dim newColumn As New Data.DataColumn("Foo", GetType(System.String))
newColumn.DefaultValue = "Your DropDownList value"
table.Columns.Add(newColumn)

C#:

System.Data.DataColumn newColumn = new System.Data.DataColumn("Foo", typeof(System.String));
newColumn.DefaultValue = "Your DropDownList value";
table.Columns.Add(newColumn);
小开 
//Data Table


protected DataTable tblDynamic
{
get
{
return (DataTable)ViewState["tblDynamic"];
}
set
{
ViewState["tblDynamic"] = value;
}
}
//DynamicReport_GetUserType() function for getting data from DB




System.Data.DataSet ds = manage.DynamicReport_GetUserType();
tblDynamic = ds.Tables[13];


//Add Column as "TypeName"


tblDynamic.Columns.Add(new DataColumn("TypeName", typeof(string)));


//fill column data against ds.Tables[13]




for (int i = 0; i < tblDynamic.Rows.Count; i++)
{


if (tblDynamic.Rows[i]["Type"].ToString()=="A")
{
tblDynamic.Rows[i]["TypeName"] = "Apple";
}
if (tblDynamic.Rows[i]["Type"].ToString() == "B")
{
tblDynamic.Rows[i]["TypeName"] = "Ball";
}
if (tblDynamic.Rows[i]["Type"].ToString() == "C")
{
tblDynamic.Rows[i]["TypeName"] = "Cat";
}
if (tblDynamic.Rows[i]["Type"].ToString() == "D")
{
tblDynamic.Rows[i]["TypeName"] = "Dog;
}
}

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