數據不能寫入excel文件

Question

我寫了代碼來讀取excel文件。當我添加聯繫人值時，我需要將這些值寫入Excel文件，但問題是這些值無法寫入Excel文件中的單元格。空白！！！！爲什麼？我的代碼有什麼問題？

static void Main(string[] args) 
    { 

     var contacts = new List<Contact>(); 

     contacts.Add(new Contact{Firstname = "name 1", Lastname = "lastname 1", Email = "email 1", PhoneNumber = "phone 1"}); 
     contacts.Add(new Contact { Firstname = "name 2", Lastname = "lastname 2", Email = "email 2", PhoneNumber = "phone 2" }); 

     Application app = new Application(); 
     // excelapp.Visible = true; 


     // _Workbook workbook = (_Workbook)(excelapp.Workbooks.Add(Type.Missing)); 
     Workbook workbook = app.Workbooks.Open(@"N:\files\transform_results.xlsx"); 
     _Worksheet worksheet = workbook.Sheets["Sheet1"]; 
     Range xlRange = worksheet.UsedRange; 
     worksheet = (_Worksheet)workbook.ActiveSheet; 


     worksheet.Cells[1, 1] = "First Name"; 
     worksheet.Cells[1, 2] = "Last Name"; 
     worksheet.Cells[1, 3] = "Email"; 


     int row = 4; 

     foreach (var contact in contacts) 
     { 


      worksheet.Cells[1, 1] = contact.Firstname; 
      worksheet.Cells[1, 2] = contact.Lastname; 
      worksheet.Cells[1, 3] = contact.Email; 
      worksheet.Cells[1, 4] = contact.PhoneNumber; 
     } 

     app.UserControl = true; 
    } 

public class Contact 
{ 
    public string Firstname { get; set; } 
    public string Lastname { get; set; } 
    public string Email { get; set; } 
    public string PhoneNumber { get; set; } 
} 

Answer 1

我測試了這個，它的工作原理。

static void Main(string[] args) 
{ 
    var contacts = new List<Contact>(); 

    contacts.Add(new Contact { Firstname = "name 1", Lastname = "lastname 1", Email = "email 1", PhoneNumber = "phone 1" }); 
    contacts.Add(new Contact { Firstname = "name 2", Lastname = "lastname 2", Email = "email 2", PhoneNumber = "phone 2" }); 

    Excel.Application app = new Excel.Application(); 
    app.Visible = true; 
    var workbook = app.Workbooks.Open(@"C:\testit.xlsx"); 
    _Worksheet worksheet = workbook.Sheets["Sheet1"]; 
    Range xlRange = worksheet.UsedRange; 
    worksheet = (_Worksheet)workbook.ActiveSheet; 

    worksheet.Cells[1, 1] = "First Name"; 
    worksheet.Cells[1, 2] = "Last Name"; 
    worksheet.Cells[1, 3] = "Email"; 

    int row = 4; 

    foreach (var contact in contacts) 
    { 
     row++; 

     worksheet.Cells[row, 1] = contact.Firstname; 
     worksheet.Cells[row, 2] = contact.Lastname; 
     worksheet.Cells[row, 3] = contact.Email; 
     worksheet.Cells[row, 4] = contact.PhoneNumber; 
    } 

    app.UserControl = true; 
    app.Quit(); 

} 

public class Contact 
{ 
    public string Firstname { get; set; } 
    public string Lastname { get; set; } 
    public string Email { get; set; } 
    public string PhoneNumber { get; set; } 
} 

Answer 2

的這段代碼...

worksheet.Cells[1, 1] 

...返回一個Range對象。你需要設置這個對象的Value2屬性來更改單元格的內容：

var cell = worksheet.Cells[1, 1]; 
cell.Value2 = contact.Firstname; 

參見：Microsoft.Office.Interop.Excel._Worksheet.Cells
人和：Microsoft.Office.Interop.Excel.Range.Value2

請注意，我已經在上面的例子非常小心not to use two dots！

Answer 3

我想補充一點，你需要小心這種類型的代碼。 使用互操作性時，您需要進行更多的內存管理。 嘗試在使用它們之前始終聲明對象，然後清除它們。 儘量不要有2點多在互操作代碼（例如object1.object2.value）

這將使（。）：

Microsoft.Office.Interop.Excel.Range _range; 
_range = worksheet.get_Range("A1", "A1"); 
_range.Value2 = contact.Firstname; 

而且完成時：

Marshal.ReleaseComObject(_range);