Shortest way to save DataTable to Textfile

Question

I just found a few answers for this, but found them all horribly long with lots of iterations, so I came up with my own solution:

Convert table to string:

string myTableAsString = 
    String.Join(Environment.NewLine, myDataTable.Rows.Cast<DataRow>().
        Select(r => r.ItemArray).ToArray().
            Select(x => String.Join("\t", x.Cast<string>())));

Then simply save string to text file, for example:

StreamWriter myFile = new StreamWriter("fileName.txt");
myFile.WriteLine(myFile);
myFile.Close();

Is there a shorter / better way?

Oneliner for saving to a file [`File.WriteAllText(location, content);`](https://msdn.microsoft.com/en-us/library/ms143375%28v=vs.110%29.aspx). There is also the predefined DataTable method [WriteXml(location)](https://msdn.microsoft.com/en-us/library/3hyx9hb4%28v=vs.110%29.aspx) that saves the content of the data table to a file. — keenthinker, Jun 01 '15 at 20:30
If you have working code it does not belong on this site. This site is for fixing broken code. — deathismyfriend, Jun 01 '15 at 20:31
If you can work with xml then you might be interested in adding the `DataTable` to `DataSet` and calling `WriteXml` on it. — rageit, Jun 01 '15 at 20:35
I just was wondering if I am not just re-inventing the wheel. If there is a very simple and short way that I just couldn't find out there, I'd appreciate if someone can let me know. The important part is about converting the table into a string, but thanks for the tip to write to a file in a single line, I didn't know it. — Leonardo Trivino, Jun 01 '15 at 20:36
It's easy to read, so I would imagine if it fits your needs and performance constraints, then there's no reason to over-engineer it. — Nate222, Jun 01 '15 at 20:40
`var dataSet = new DataSet(); dataSet.Add(new DataTable()); dataSet.WriteXml("filename.xml");` — rageit, Jun 01 '15 at 20:42

score 15 · Accepted Answer · answered Jun 01 '15 at 20:45

15

You have your DataTable named as myDataTable, you can add it to DataSet as:

var dataSet = new DataSet();
dataSet.AddTable(myDataTable);

// Write dataset to xml file or stream
dataSet.WriteXml("filename.xml");

And you can also read from xml file or stream:

dataSet.ReadXml("filename.xml");

answered Jun 01 '15 at 20:45

rageit

3,513
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2

Why do you need to create the DataSet? Can't you just do `myDataTable.WriteXml("filename.xml")` as someone else suggested? – Leonardo Trivino Jun 01 '15 at 20:52
3

For some reason I was thinking about multiple tables. If you need just one table to be written then certainly you can go with `DataTable.WriteXml`. – rageit Jun 01 '15 at 20:56
1

FYI: In .NET Framework 4.6.2, there is no method on `System.Data.DataSet` named `AddTable` I used the `Add` method on `DataSet.Tables`. See [.NET Framework 4.6.2 Documentation for DataSet](https://learn.microsoft.com/en-us/dotnet/api/system.data.dataset?view=netframework-4.6.2) and [.NET Framework 4.6.2 Documentation for DataTableCollection.Add](https://learn.microsoft.com/en-us/dotnet/api/system.data.datatablecollection.add?view=netframework-4.6.2) – qxotk Sep 11 '19 at 15:39

score 2 · Answer 2 · answered Jun 01 '15 at 20:35

@Leonardo sorry but i can 't comment so i post.

Sometimes you can ask the dataset and then work with it. Like this:

foreach (DataRow row in ds.Tables[0].Rows)
{
    foreach (object item in row.ItemArray)
    {
        myStreamWriter.Write((string)item + "\t");
    }
    myStreamWriter.WriteLine();
}

That 's another way but i don 't know which 'll give you a better metric.

score 2 · Answer 3 · answered Jun 01 '15 at 20:43

2

If you consider XML as text you can do: myDatatable.WriteXml("mydata.xml") and myDatatable.ReadXml("mydata.xml")

answered Jun 01 '15 at 20:43

rlee

293
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8

Yes, this looks much simpler too. – Leonardo Trivino Jun 01 '15 at 20:48

score 2 · Answer 4 · answered Feb 04 '19 at 16:00

You get an error unless you save it with the schema:

myDataTable.WriteXml("myXmlPath.xml", XmlWriteMode.WriteSchema);
myDatatable.ReadXml("myXmlPath.xml");

There is more info on saving/loading with schema here: DataTable does not support schema inference from Xml.?

Shortest way to save DataTable to Textfile

4 Answers4

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