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copy content of one DataTable to another without using clone or copy

I want to copy the content from one datatable to another without copying or cloning the data structure. what is the best way to do this?
I need to do it this way because I am given a datatable from a SQL server stored procedure and I cannot amend the given read only table. so I need recreate it without copying all the underlying structure.
I hope that makes sense.
Regards
Amarino

If you want to copy dataTable you have two options first one is copy or clone.
The second option is using foreach or for loop to copy you can get any columns from dataTable
int columnsize = dt.Columns.Count;
foreach (DataRow X in dt.Rows)
{
for (int i = 0; i < columnsize; i++)
{
// int bir = Convert.ToInt32(X[i]);
// you can set here your need dataTable
}
}
// then here new dataTable you can assing to any datagridview.DataSource = newDataTable
but in the second case you should know ahead what data will come in which place to look this you can get any cell and assing it new DataTable
here is my using code
DataTable dh1 = new DataTable("data1");
dh1.Columns.Add("specification_name", typeof(string));
dh1.Columns.Add("summalar", typeof(string));
dh1.Columns.Add("address", typeof(string));
dh1.Columns.Add("id1", typeof(int));
dh1.Columns.Add("client_id", typeof(int));
dh1.Columns.Add("stack_id", typeof(int));
foreach (DataRow dd in dt.Rows)
{
DataTable temp = new DataTable("temp");
DataRow ttt = dh1.NewRow();
for (int j = 0; j < col; j++)
{
ttt[0] = dd[1];
ttt[1] = dd[2];
ttt[2] = dd[3];
ttt[3] = dd[4];
ttt[4] = dd[5];
ttt[5] = dd[6];
break;
}
dh1.Rows.Add(ttt);
}

I was looking to do something like this: The below solution works for me.
DataTable lDT2 = someMethod(); //populated with data from SomeMethod()
DataTable lDT3 = new DataTable();
lDT3.Columns.Add("Name", typeof(string));
lDT3.Columns.Add("Name2", typeof(string));
foreach (DataColumn col in lDT2.Columns) {
lDT3.Columns.Add(col.ColumnName, col.DataType);
}
foreach (DataRow dr in lDT2.Rows) {
DataRow lDT3dr = lDT3.NewRow();
for (int i = 0; i < lDT2.Columns.Count; i++) {
if (i == 0) { lDT3dr[i] = "some info"; }
if (i == 1) { lDT3dr[i] = "more info"; }
lDT3dr[i+2] = dr[i];
}
lDT3.Rows.Add(lDT3dr);
}

If I understand correctly you want to copy the data but ignore the schema. You can do this by gathering data set from the source table then iterate through each row and insert it into the destination table.
This is a simple way to copy data from one table to another without any worry of keys or constraints. You will need to make sure your destination table can accept the data (it must be of the correct type or you must cast it to something acceptable).

Another option is to use DefaultView.ToTable(). This also allows you to pull DISTINCT values. If you want all columns
var myNewTable = ExistingDataTable.DefaultView().ToTable();
If you wanted to limit for some criteria
var dv = ExistingDataTable.DefaultView();
dv.Filter = "SomeColumn = 'SomeValue'";
var myFilteredTable = dv.ToTable();

How to rows dynamically in datagrid C# wpf?

I want to set number of rows of datagrid equal to a number given by user in a textbox.
means if i enter 6 in the textbox, it should add 6 rows in the datagrid.
thats what i want. I may be wrong.
But Null exception is being thrown.
How to fix my issue?
Here is the code:
DataTable dt;
DataRow dr;
int rownumber=0;
dt = new DataTable("emp2");
DataColumn dc3 = new DataColumn("Wi", typeof(double));
DataColumn dc4 = new DataColumn("Hi", typeof(double));
rownumber = Int32.Parse(txtBexNumber.Text);
dr[rownumber] = dt.NewRow();
dt.Rows.Add(dr);
dt.Columns.Add(dc3);
dt.Columns.Add(dc4);
datagrid1.ItemsSource = dt.DefaultView;

You're creating a DataTable, then trying to immediately access a user-specified row in the table even though no rows have been added yet.
Use a loop to add rows first
for(int i = 0; i < rowNumber; i++)
{
dr = dt.NewRow();
dt.Rows.Add(dr);
}
As a side note, when working with WPF its easier to work with an ObservableCollection of objects instead of DataTables and DataRows. The data is much easier to understand and work with instead of trying to use DataRows and DataColumns.
var data = new ObservableCollection<MyObject>();
for (int i = 0; i < rowNumber; i++)
data.Add(new MyObject() { Wi = 0, Hi = 0 });
dataGrid1.ItemsSource = data;

I guess it´s better to use
Int32.TryParse(txtBexNumber.Text, out rownumber);
(maybe you get the error for parsing an empty string? If possible try to debug where exactly the null pointer exception accurs)
Also validate if
dr[rownumber] = dt.NewRow();
works as expected. If e.g. dr[10] doesn´t exist, you get an exception.

How to programmatically add rows to DataGrid in C#?

So as the title states, I'm trying to add rows to a DataGrid programmatically using C# but I can't seem to make it work. This is what I have so far.
// I have a DataGrid declared as dg in the XAML
foreach (string s in array) {
int index = 0;
DataGridRow dgRow = new DataGridRow();
foreach (DataGridColumn dgColumn in columns)
{
// Trying to add Text to dgRow here but IDK how
index++;
}
}
I've been googling around and the closest I got to adding anything was to use {column = value} but it just throws me an error. Really out of ideas now though :\

Here's you can do it better way by binding a source to datagridview
// Creating DataSource here as datatable having two columns
DataTable dt = new DataTable();
dt.Columns.Add("ID", typeof(int));
dt.Columns.Add("Name");
// Adding the rows in datatable
for (int iCount = 1; iCount < 6; iCount++)
{
var row = dt.NewRow();
row["ID"] = iCount;
row["Name"] = "Name " + iCount;
dt.Rows.AddRow(row);
}
DataGridView dgv = new DataGridView();
// Set AutoGenerateColumns true to generate columns as per datasource.
dgv.AutoGenerateColumns = true;
// Finally bind the datasource to datagridview.
dgv.DataSource = dt;
In Case you are using WPF DataGrid
you can bind it like this way-
dgv.DataContext = employeeData.DefaultView;
and in
XAML
<DataGrid Name="dgv" ItemsSource="{Binding}">

//create datatable and columns,
DataTable dtable = new DataTable();
dtable.Columns.Add(new DataColumn("Column 1"));
dtable.Columns.Add(new DataColumn("Column 2"));
//simple way create object for rowvalues here i have given only 2 add as per your requirement
object[] RowValues = { "", "" };
//assign values into row object
RowValues[0] = "your value 1";
RowValues[1] = "your value 2";
//create new data row
DataRow dRow;
dRow = dtable.Rows.Add(RowValues);
dtable.AcceptChanges();
//now bind datatable to gridview...
gridview.datasource=dbtable;
gridview.databind();
Regards

did you try?:
int n=5; // number of rows you want to add
dataGridView1.Rows.Add(n);
// you can add (names of the rows) if you have them in your array
//for(int i=0; i<n; i++)
//dataGridView1[0, i].Value = array[i];

How to bind DataRow from DataSet?

I have a DataSet that contains values returned by my WCF function, as below:
DataSet ds = IserviceClient.FunctionMe(dcClient, dcBook);
#region show to dgv_item
DataTable dt1 = ds.Tables[0];
DataRow dr1;
int rc = dt1.Rows.Count;
clsMessageBoxes.ShowInfo(rc.ToString()); // Here show the number of row, so far the row is show the right value
//from here how to pass the row in that datatable to my datagridview? i
for (int i = 0; i < rc; i++)
{
dr1 = dt1.Rows[i];
dgv_item.Rows.Add();
dgv_item.Rows[i].Cells["dgvc_no"].Value = dr1["cnNo"].ToString();
dgv_item.Rows[i].Cells["dgvc_ID"].Value = dr1["cnID"].ToString();
dgv_item.Rows[i].Cells["dgvc_Name"].Value = dr1["cnName"].ToString();
}
Using this, I get the error
Rows cannot be programmatically added to datagridview's rows collection when the control is data-bound
Why do I get this, and how can I resolve it?

Getting a dataset from an unbound datagridview

I have a datagridview that is not bound directly do a datasource. Instead, I add the data from various methods during runtime. I created a method that accepts a dataSet and outputs it into Excel, but I can't find if there is an in-built way to geta dataSet from a dataGridView.
Thanks.

I updated the code to work. There was a few typos in the previous answer.
DataTable dt = new DataTable();
for (int i = 0; i < dgvPaperAndPlastic.Columns.Count; i++)
{
DataColumn column = new DataColumn(dgvPaperAndPlastic.Columns[i].HeaderText);
dt.Columns.Add(column);
}
int noOfColumns = dgvPaperAndPlastic.Columns.Count;
foreach (DataGridViewRow dr in dgvPaperAndPlastic.Rows)
{
//Create table and insert into cell value.
DataRow dataRow = dt.NewRow();
for (int i = 0; i < noOfColumns; i++)
{
dataRow[i] = dr.Cells[i].Value.ToString();
}
}