Dynamic Function

I want to write a function, which accept 3 parameters, 1 TableName 2 ColumnName 3 DateValue,
and returns number of records in that table for that particular date(in parameter date), 
I have written below function but it is not returning the desired result, can anyone help me.
CREATE FUNCTION dbo.[f_Rec_cnt] 
	(@InTableName NVARCHAR(100),
	 @InDtColName NVARCHAR(50),
	 @InDate NVARCHAR(50)
        )
RETURNS INT
AS
BEGIN
DECLARE @vRowCnt NVARCHAR(50)
DECLARE @vTableName NVARCHAR(150)
DECLARE @vDtColName NVARCHAR(50)
DECLARE @vInDate NVARCHAR(50)
DECLARE @vSql NVARCHAR(500)
SELECT @vTableName=@InTableName,@vDtColName=@InDtColName,@vInDate=@InDate
      SELECT @vInDate=''''+CAST(@InDate AS NVARCHAR)+''''
      SELECT @vSql='SELECT @vRowCnt = COUNT(*) FROM '+@vTableName+' WHERE '+@vDtColName+'='+@vInDate
      EXECUTE SP_EXECUTESQL @vSql
      RETURN (CAST(@vRowCnt AS INT))
END