2013-08-23 79 views
0

在我的應用程序中,我不明白如何處理system.format異常。請參見下面的代碼句柄system.format異常C#

public Harvest_Project(XmlNode node) 
    { 
     this._node = node; 
     this._name = node.SelectSingleNode("name").InnerText; 

     this._created_at = storeTime(node.SelectSingleNode("created-at").InnerText); 
     this._updated_at = storeTime(node.SelectSingleNode("updated-at").InnerText); 
     this._over_budget_notified_at = storeTime(node.SelectSingleNode("over-budget-notified-at").InnerText); 
     this._latest_record_at = storeTime(node.SelectSingleNode("hint-latest-record-at").InnerText); 
     this._earliest_record_at = storeTime(node.SelectSingleNode("hint-earliest-record-at").InnerText); 

     this._billable = bool.Parse(node.SelectSingleNode("billable").InnerText); 

     try 
     { 
       this._id = Convert.ToInt32(node.SelectSingleNode("id").InnerText); 
       this._client_id = Convert.ToInt32(node.SelectSingleNode("client-id").InnerText); 
       this._budget = float.Parse(node.SelectSingleNode("budget").InnerText); 
       this._fees = Convert.ToInt32(getXmlNode("fees", node)); 

     } 
     catch (FormatException e) 
     { 

      Console.WriteLine(); 
     } 
     catch (OverflowException e) 
     { 
      Console.WriteLine("The number cannot fit in an Int32."); 
     } 

     this._code = node.SelectSingleNode("code").InnerText; 
     this._notes = node.SelectSingleNode("notes").InnerText; 

    } 

在這裏,嘗試和catch塊,所有的節點需要int類型,但是,作爲_fees以「0」值。它顯示我格式異常。我只想讓我的節點不顯示空字符串。我想處理這個異常。這意味着,它不應該拋出異常在「this._fees = Convert.ToInt32(getXmlNode(」fees「,node));」因爲它返回我想要的int值。

我怎麼能做到這一點?

回答

5

您可以avoidcontrol-flowprogrammingtry/catch機制一般通過使用TryX方法;你的情況,int.TryParse,使得:

int output; 
if (int.TryParse(input, out output)) { 
    // success 
} else { 
    // failure 
} 
+2

[文檔在這裏(http://msdn.microsoft.com/en-us/library/f02979c7.aspx) – tnw

+0

我是WPF的新手,我應該在哪寫這篇文章? – user2622971

0

你還沒有發佈的XML,我無法找到getXmlNode功能
但我beleive,它返回的XmlNode有一個其他內容則正好詮釋(否則,你會使用InnerText屬性

就試試這個:

XmlNode fees = getXmlNode(...) 
var curr = fees.FirstChild; 
int _fees = 0; 
while (curr != null) { 
    _fees += (Convert.ToInt32(curr.InnerText); 
    curr = curr.NextSibling(); 
}