Excel unable to insert more than 255 chars?

问题:

I am using OLE DB driver to insert more than 255 characters into an Excel sheet, but I get the error:

Exception Details: System.Data.OleDb.OleDbException: The field is too small to accept the amount of data you attempted to add. Try inserting or pasting less data.

Seems from this thread that it's an Excel limitation. Even the Microsoft site seems to say so here.

So does this mean I can't programmatically, but I can manually? Because I can enter more than 255 characters when I manually type them in Excel. So is it a Microsoft.ACE.OLEDB.12.0(AccessDatabaseEngine.exe) driver limitation?

回答1:

The link you are refering to, is about 256 columns and not characters. The 256 characters problem is described here with a workaround: http://support.microsoft.com/kb/213841

回答2:

I found a more efficient way to handle this problem, my references are the 2 links below

http://support.microsoft.com/kb/316934

http://www.codeproject.com/Articles/37055/Working-with-MS-Excel-xls-xlsx-Using-MDAC-and-Oled

Basically do not use data adapter, data set and parameters to insert rows in the Excel (this never worked for me) instead run SQL insert from the code directly using command object

Here what you have to do

1. Declare the wide field as MEMO instead of string or CHAR "CREATE TABLE WorkSheetName ( field1 INT, field2 MEMO, field3 ... );"
2. Build the insert statement like "INSERT INTO WorkSheetName (field1, field2, ...) VALUES (1234, 'Any long string here...', ...)"

3. Declare a DbCommand to run the Create table and Insert statements above, here I am using the command obj from enterprise library

   DbCommand dbCommand = m_dbConnection.CreateCommand(); dbCommand.CommandText = "Create Table ..."; dbCommand.CommandType = CommandType.Text; dbCommand.ExecuteNonQuery();

   dbCommand.CommandText = "Insert Into ..."; dbCommand.CommandType = CommandType.Text; dbCommand.ExecuteNonQuery();

回答3:

My workaround to this issue is to add a text which its length is longer than 255 characters on the first row of the column. OleDB will treat this column as MEMO type and then it can insert more than 255 characters in a cell.