Every one know that CSV file stores the tabular data in plain text format.A CSV file consists of any number of records, separated by line breaks of some kind; each record consists of fields, separated by some other character or string, most commonly a literal comma or tab. Usually, all records have an identical sequence of fields. I have a requirement like I want to read the CSV file and Convert to Collection of objects. Steps to convert the CSV file to collection as follows.
- Read all the lines from the CSV file
- Take the first line as the header and remaing lines as records
- Convert the data to data table by parsing first line to data columns and remaining lines to data rows
- Convert data table to collection
Sample code to implement step 1 to 3
public static DataTable ToDataTable(string csvFileNameIncludingPath) { var dt = new DataTable(); var s = File.ReadAllLines(csvFileNameIncludingPath); string[] tableData = s.Split("\r\n".ToCharArray(), StringSplitOptions.RemoveEmptyEntries); var col = from cl in tableData[0].Split(",".ToCharArray()) select new DataColumn(cl.TrimStart('"').TrimEnd('"')); // In my case all the field values are included in the double quotes ex: "FirstName". So used TrimStart and TrimEnd methods to remove double quotes dt.Columns.AddRange(col.ToArray()); (from st in tableData.Skip(1) select dt.Rows.Add(st.Split(",".ToCharArray()).Select(str => str.TrimStart('"').TrimEnd('"')).ToArray())).ToList(); // In my case all the field values are included in the double quotes ex: "jhon". So used TrimStart and TrimEnd methods to remove double quotes return dt; }Sample code to implement step 4
public static List<T> ToCollection<T>(this DataTable dt, IList<KeyValuePair<string, string>> changedNames = null) // changeNames parameter used for mapping the column name change with object propertyname { List<T> lst = new List<T>(); Type tClass = typeof(T); PropertyInfo[] pClass = tClass.GetProperties(); List<DataColumn> dc = dt.Columns.Cast<DataColumn>().ToList(); T cn; foreach (DataRow item in dt.Rows) { cn = (T)Activator.CreateInstance(tClass); foreach (PropertyInfo pc in pClass) { // Can comment try catch block. try { DataColumn d = dc.Find(c => c.ColumnName == pc.Name || (changedNames != null && changedNames.Any(x => x.Key == c.ColumnName))); var ds = dc.Where(x => x.ColumnName == pc.Name); if (d != null) pc.SetValue(cn, item[pc.Name], null); } catch { } } lst.Add(cn); } return lst; }I hope this will helps you.
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