Check if value exists in dataTable?

c# datatable
valterriann picture valterriann · May 22, 2012 · Viewed 242.1k times · Source

I have DataTable with two columns Author and Bookname.

I want to check if the given string value Author already exists in the DataTable. Is there some built in method to check it, like for Arrays array.contains?

Answer

Tim Schmelter picture Tim Schmelter · May 22, 2012

You can use LINQ-to-DataSet with Enumerable.Any:

String author = "John Grisham";
bool contains = tbl.AsEnumerable().Any(row => author == row.Field<String>("Author"));

Another approach is to use DataTable.Select:

DataRow[] foundAuthors = tbl.Select("Author = '" + searchAuthor + "'");
if(foundAuthors.Length != 0)
{
    // do something...
}

Q: what if we do not know the columns Headers and we want to find if any cell value PEPSI exist in any rows'c columns? I can loop it all to find out but is there a better way? –

Yes, you can use this query:

DataColumn[] columns = tbl.Columns.Cast<DataColumn>().ToArray();
bool anyFieldContainsPepsi = tbl.AsEnumerable()
    .Any(row => columns.Any(col => row[col].ToString() == "PEPSI"));

Related questions

LINQ query on a DataTable

I'm trying to perform a LINQ query on a DataTable object and bizarrely I am finding that performing such queries on DataTables is not straightforward. For example: var results = from myRow in myDataTable where results.Field("RowNo") == 1 select results; This …

Read More
How to create a DataTable in C# and how to add rows?

How do create a DataTable in C#? I did like this: DataTable dt = new DataTable(); dt.clear(); dt.Columns.Add("Name"); dt.Columns.Add("Marks"); How do I see the structure of DataTable? Now I want to add ravi for …

Read More
How to select distinct rows in a datatable and store into an array

I have a dataset objds. objds contains a table named Table1. Table1 contains column named ProcessName. This ProcessName contains repeated names.So i want to select only distinct names.Is this possible. intUniqId[i] = (objds.Tables[0].Rows[i]["ProcessName"].ToString());

Read More