Datenbindung Nullwerte zurückgeben

Question

Ich versuche also, eine Excel-Datei zu lesen und die Daten in Klasseneigenschaften einzufügen. Ich denke, es gibt ein Problem, wenn ich die Klasse instanitae, aber ich mache es, bevor ich analysieren und die Werte der Klasse hinzufügen.

Sobald das Parsing abgeschlossen ist - ich rufe die gebundene Klasse, aber es gibt null zurück.

The Calls

 TestData td = new TestData(); 

     XLReader.GetClassFromExcel<TestData>(1,1,1); 

     var ddddd = td.Title; //this is null. 

Die Klasse

public class TestData 
{ 
    public string Title { get; set; } 
    public string Site { get; set; } 
    public string StartDate { get; set; } 
    public string EndDate { get; set; } 
    public string Email { get; set; } 
    public string OrderRef { get; set; } 
    public string ReqBy { get; set; } 
    public string ApprovedBy { get; set; } 

} 

Die Parsing des Excel

public static class XLReader 
{ 
    /// <summary> 
    /// The deployment files folder name 
    /// </summary> 
    private static readonly string deploymentFilesFolderName = 
     Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location); 

    public static List<T> GetClassFromExcel<T>(int fromRow, int fromColumn, int toColumn = 0) 
    { 

     var path = Path.Combine(deploymentFilesFolderName, @"Tools\TestData.xlsx"); 
     List<T> retList = new List<T>(); 
     using (var pck = new ExcelPackage()) 
     { 
      using (var stream = File.OpenRead(path)) 
      { 
       pck.Load(stream); 
      } 
      //Retrieve first Worksheet 
      var ws = pck.Workbook.Worksheets.First(); 
      //If the to column is empty or 0, then make the tocolumn to the count of the properties 
      //Of the class object inserted 
      toColumn = toColumn == 0 ? typeof(T).GetProperties().Count() : toColumn; 

      //Read the first Row for the column names and place into a list so that 
      //it can be used as reference to properties 
      List<string> columnNames = new List<string>(); 
      // wsRow = ws.Row(0); 
      foreach (var cell in ws.Cells[1, 1, 1, ws.Cells.Count()]) 
      { 
       columnNames.Add(cell.Value.ToString()); 
      } 

      //Loop through the rows of the excel sheet 
      for (var rowNum = fromRow; rowNum <= ws.Dimension.End.Row; rowNum++) 
      { 
       //create a instance of T 
       T objT = Activator.CreateInstance<T>(); 
       //Retrieve the type of T 
       Type myType = typeof(T); 
       //Get all the properties associated with T 
       PropertyInfo[] myProp = myType.GetProperties(); 

       var wsRow = ws.Cells[rowNum, fromColumn, rowNum, ws.Cells.Count()]; 

       foreach (var propertyInfo in myProp) 
       { 
        if (columnNames.Contains(propertyInfo.Name)) 
        { 
         int position = columnNames.IndexOf(propertyInfo.Name); 
         //To prevent an exception cast the value to the type of the property. 
         var blah = Convert.ChangeType(wsRow[rowNum, position + 1].Value, propertyInfo.PropertyType); 
         propertyInfo.SetValue(objT,blah); 

        } 
       } 

       retList.Add(objT); 
      } 

     } 
     return retList; 
    } 
} 

Answer 1

Wh en I Excel-Daten importieren, erstelle ich immer einen String-Array den Wert mit diesem Code speichern

package.Load(fileContent.InputStream); 
ExcelWorksheet workSheet = package.Workbook.Worksheets[1]; 

int totalRows = workSheet.Dimension.End.Row; 
int totalCols = workSheet.Dimension.End.Column; 
List<myObject> listMyObject = new List<myObject>(); 
for (int currentRow = 1; currentRow <= totalRows; currentRow++) 
{ 
    string[] resultRow = new string[totalCols]; 
    for (int currentCol = 1; currentCol <= totalCols; currentCol++) 
    { 
     //We read the entire line and store it in the array 
     resultRow[currentCol - 1] = (workSheet.Cells[currentRow, currentCol].Value != null) ? workSheet.Cells[currentRow, currentCol].Value.ToString() : ""; 
    } 

    //And now I can bind my array to my object 
    listMyObject.Add(myObjectHelper.Convert(resultRow)); 
} 
//Here i've got my list object 

wird mein Array im schlimmsten Fall eine leere Zeichenfolge enthält. In diesem Fall weiß ich, dass in meiner Excel-Datei nichts eingetragen ist.

Und nachdem ich meine String-Array zu meinem Objekt konvertieren