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

C#asp.net.NetVisual Studio-2008Datatable

C# Problem Overview


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?

C# Solutions


Solution 1 - C#

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);

Solution 2 - C#

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;

Solution 3 - C#

//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;
                    }
                }
            

Attributions

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Content TypeOriginal AuthorOriginal Content on Stackoverflow
QuestionthevanView Question on Stackoverflow
Solution 1 - C#Keith WaltonView Answer on Stackoverflow
Solution 2 - C#Tim SchmelterView Answer on Stackoverflow
Solution 3 - C#Dhiraj ShejaleView Answer on Stackoverflow