循環UIElement變量名稱

Question

我嘗試在WPF應用程序中循環我的食物對象的名稱。

我想foo​​delement的名稱如下：food0，食物1，foot2 ...

for (int i = 0; i < foods.Count; i++) 
{ 
    System.Windows.UIElement foodelement = "food" + i; // ERROR here 
    Canvas.SetLeft(foodelement, foods[i].Position.X); 
} 

我得到的錯誤： Cannot implicitly convert type string to System.Windows.UIElement

Answer 1

這可能會幫助你

System.Windows.UIElement foodelement = (System.Windows.UIElement)YourContainer.FindName("food" + i); 

其中YourContainer是容納UIElements的容器（網格/畫布/堆棧面板/）。

否則，您可以使用下列內容：

System.Windows.UIElement foodelement = UIHelper.FindChild<System.Windows.UIElement>(Application.Current.MainWindow, "food" + i); 

Answer 2

我認爲下面的代碼將幫助您

/// <summary> 
/// Finds a Child of a given item in the visual tree. 
/// </summary> 
/// <param name="parent">A direct parent of the queried item.</param> 
/// <typeparam name="T">The type of the queried item.</typeparam> 
/// <param name="childName">x:Name or Name of child. </param> 
/// <returns>The first parent item that matches the submitted type parameter. 
/// If not matching item can be found, 
/// a null parent is being returned.</returns> 
public static T FindChild<T>(DependencyObject parent, string childName) 
    where T : DependencyObject 
{ 
    // Confirm parent and childName are valid. 
    if (parent == null) return null; 

    T foundChild = null; 

    int childrenCount = VisualTreeHelper.GetChildrenCount(parent); 
    for (int i = 0; i < childrenCount; i++) 
    { 
     var child = VisualTreeHelper.GetChild(parent, i); 
     // If the child is not of the request child type child 
     T childType = child as T; 
     if (childType == null) 
     { 
      // recursively drill down the tree 
      foundChild = FindChild<T>(child, childName); 

      // If the child is found, break so we do not overwrite the found child. 
      if (foundChild != null) break; 
     } 
     else if (!string.IsNullOrEmpty(childName)) 
     { 
      var frameworkElement = child as FrameworkElement; 
      // If the child's name is set for search 
      if (frameworkElement != null && frameworkElement.Name == childName) 
      { 
       // if the child's name is of the request name 
       foundChild = (T)child; 
       break; 
      } 
     } 
     else 
     { 
      // child element found. 
      foundChild = (T)child; 
      break; 
     } 
    } 

    return foundChild; 
} 

，並使用此方法

for (int i = 0; i < foods.Count; i++) 
     { 
     System.Windows.UIElement ui = FindChild<Button>(Application.Current.MainWindow, "food" + i); 
     }