Reputation: 11816
its my first time to access and read an excel file (xlsx) with c#.. i am having problem and the error was: No value given for one or more required parameters
below is my code:
private void button5_Click(object sender, EventArgs e)
{
string ConnectionString = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\Class Schedules.xlsx;Extended Properties=""Excel 12.0;HDR=NO;""";
string ExcelQuery;
ExcelQuery = "SELECT A1 FROM [Sheet1$]";
OleDbConnection ExcelConnection = new OleDbConnection(ConnectionString);
ExcelConnection.Open();
OleDbCommand ExcelCommand = new OleDbCommand(ExcelQuery, ExcelConnection);
OleDbDataReader ExcelReader;
ExcelReader = ExcelCommand.ExecuteReader(); //error happens here
while (ExcelReader.Read())
{
MessageBox.Show((ExcelReader.GetValue(0)).ToString());
}
ExcelConnection.Close();
}
since this is my first time, im just trying to read the content of A1, below is my excel file:
but running the code would give me an error: No value given for one or more required parameters.
Upvotes: 2
Views: 8381
Reputation: 11816
okay, i found a way to read a specific cell in c#....
location rCnt=1,cCnt=1
is A1
in excel
private void button9_Click(object sender, EventArgs e)
{
Excel.Application xlApp;
Excel.Workbook xlWorkBook;
Excel.Worksheet xlWorkSheet;
Excel.Range range;
string str;
int rCnt = 1; // this is where you put the cell row number
int cCnt = 1; // this is where you put the cell column number
xlApp = new Excel.ApplicationClass();
xlWorkBook = xlApp.Workbooks.Open(@"C:\Class Schedules.xlsx", 0, true, 5, "", "", true, Microsoft.Office.Interop.Excel.XlPlatform.xlWindows, "\t", false, false, 0, true, 1, 0);
xlWorkSheet = (Excel.Worksheet)xlWorkBook.Worksheets.get_Item(1);
range = xlWorkSheet.UsedRange;
str = (string)(range.Cells[rCnt, cCnt] as Excel.Range).Value2; //you now have the value of A1.
xlWorkBook.Close(true, null, null);
xlApp.Quit();
releaseObject(xlWorkSheet);
releaseObject(xlWorkBook);
releaseObject(xlApp);
}
private void releaseObject(object obj)
{
try
{
System.Runtime.InteropServices.Marshal.ReleaseComObject(obj);
obj = null;
}
catch (Exception ex)
{
obj = null;
MessageBox.Show("Unable to release the Object " + ex.ToString());
}
finally
{
GC.Collect();
}
}
be sure to have:
using Excel = Microsoft.Office.Interop.Excel;
and add a reference into the project called Microsoft Excel Object Library which can be found under the COM tab... if you want to read multiple texts, just use for loop and increment value of rCnt or cCnt... if you want to write into the cell, i think it could be done this way:
(range.Cells[rCnt, cCnt] as Excel.Range).Value2 = value;
that's all...hope this will help others
Upvotes: 1
Reputation: 2535
I believe the A1 in your query is the problem. To test just try the following and see it eliminates the error...
ExcelQuery = "SELECT * FROM [Sheet1$]";
If you want to select specific columns then use HDR=YES instead (in your conn string).
string ConnectionString = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\Temp\Class Schedules.xlsx;Extended Properties=""Excel 12.0;HDR=YES;""";
This signals that the first row of your sheet contains the column names. So it requires your sheet in question be formatted this way but then you can select specific columns...
ExcelQuery = "SELECT [Time] FROM [Sheet1$]";
Upvotes: 0
Reputation: 66398
From looking in some old code I have, the syntax should be:
ExcelQuery = "SELECT * FROM A1:Q10000";
Meaning you don't have to specify the sheet name, it will always take from the first or default sheet and you have to specify the range of columns you select as well.
Upvotes: 0