Reading and Writing Data

You can read and write data from and to your spreadsheet in a few different ways. The most obvious is to use the Cells property of the ExcelWorksheet class, shown on the Getting Started page. There are also a few other ways to import/export/read data from/into spreadsheets with EPPlus.

From the Cells property (ExcelRange) you can access these methods to load data from various sources:

• LoadFromText and LoadFromTextAsync- Read a csv text file and load the data into a range on a worksheet.
• LoadFromDataReader and LoadFromDataReaderAsync - Loads data into a range from a DataReader
• LoadFromDataTable - Loads data into a range from a DataTable. Can be used for importing data from a range of sources, like XML (example provided) and databases.
• LoadFromCollection - Loads data into a range from an IEnumerable using reflection.
• LoadFromDictionaries - Loads data into a range from an IEnumerable of ExpandoObject/dynamic objects (via their IDictionary<string, object> interface. Useful for importing json data, example provided.
• LoadFromArrays - Loads data into a range from an IEnumerable of object[] where each object array becomes a row in the worksheet.

You can optionally specify a parameter to create an ExcelTable when you use these methods. For more detailed examples, have a look at sample 4 & 5 the sample project Sample-.NET Framework or Sample-.NET Framework.

From the Cells property (ExcelRange) you can access these methods to write:

• ToText and ToTextAsync - Writes a range to a csv string.

• SaveToText and SaveToTextAsync - Writes a range to a csv file.

• GetValue<T> - Gets a value, with the option to specify a datatype

• Value - Gets or sets the value of the range.

You can also use the GetValue and SetValue methods directly on the worksheet object. (This will give a little bit better performance than reading/writing via the range):

• GetValue<T> - Gets a value of a single cell, with the option to specify a datatype
• SetValue - Sets a value of a single cell

Since the Cells property implements the IEnumerable interface, you can use Linq to query data from a worksheet.

var query1= (from cell in sheet.Cells["d:d"] where cell.Value is double && (double)cell.Value >= 9990 && (double)cell.Value <= 10000 select cell);

Most of these methods are demonstrated in the sample project.