db null進來屬性asp.net

Question

我在代碼中得到錯誤獲取錯誤 表'wsm_View_PurchaseOrderList'中'TotalValue'列的值是DBNull。

error image

public decimal TotalValue { 
    get { 

     try { 
      if (object.ReferenceEquals(tablewsm_View_PurchaseOrderList.TotalValueColumn, DBNull.Value)) { 
       return 0.0; 
      } else { 
       return Convert.ToDecimal(this(this.tablewsm_View_PurchaseOrderList.TotalValueColumn)); 
      } 

     } catch (System.InvalidCastException e) { 
      throw new global::System.Data.StrongTypingException("The value for column 'TotalValue' in table 'wsm_View_PurchaseOrderList' is DBNull" + ".", e); 
     } 
    } 
    set { this(this.tablewsm_View_PurchaseOrderList.TotalValueColumn) = value; } 
} 

Answer 1

建議您檢查您的DBNull這樣的：

if (Convert.IsDBNull(tablewsm_View_PurchaseOrderList.TotalValueColumn)) 
{ 
    return 0.0; 
}