SSIS For Loop - Wait for file to carry on - for-loop

Question

I am creating an SSIS package that imports 10 different CSV files, however the availability of each file varies - so i want to get the file check to loop until all files are there and then start to import process.
I check this through a T-SQL script
IF OBJECT_ID('tblFileCheck') IS NOT NULL
DROP TABLE tbFileCheck;
CREATE TABLE tblFileCheck (
id int IDENTITY(1,1)
,subdirectory nvarchar(512)
,depth int
,isfile bit);
INSERT tblFileCheck
EXEC xp_dirtree '\\reports\Reports\CSV', 10, 1
BEGIN
IF EXISTS (
SELECT COUNT(id)
FROM tblFileCheck
HAVING count(id) > 9
)
BEGIN
PRINT 'Success - Import Latest File'
END
ELSE
BEGIN
RAISERROR ('Looping back to start - insufficient files to run', 16, 1 );
END
END
However I cant get the loop to work, I have created a variable varWaitForData (int32, val = 0), created a SQL task editor with result set = single row and set the result set option to the parameter.
Set the InitExpression #varWaitForData = 0 AND EvalExpression #varWaitForData == 0.
But i keep getting the error [Execute SQL Task] Error: An error occurred while assigning a value to variable "varWaitForData": "Exception from HRESULT: 0xC0015005".

Answer 1

I would use a different approach:
set up a variable called fileCount as int
script task: Get file count
System.IO.DirectoryInfo dir = new System.IO.DirectoryInfo("\\reports\Reports\CSV");
Dts.Variables["User::fileCount"].Value = dir.GetFiles().Length;
Now set up a foreach file enumerator
and put a constraint on the path that fileCount > 9