共用方式為

FormViewDesigner.GetDesignTimeHtml 方法

  • 參考

定義

命名空間:
System.Web.UI.Design.WebControls
組件:
System.Design.dll

取得在設計階段用來呈現關聯控制項的標記。

public:
 override System::String ^ GetDesignTimeHtml();
public override string GetDesignTimeHtml ();
override this.GetDesignTimeHtml : unit -> string
Public Overrides Function GetDesignTimeHtml () As String

傳回

String

String，包含在設計階段用來呈現 FormView 的標記。

範例

下列程式代碼範例示範如何在設計時間覆寫 GetDesignTimeHtml 繼承自 FormViewDesigner 類別的 類別中的方法，以變更控件的外觀 FormView 。 如果已定義 ，Caption此範例會將新的第一個數據列加入方格，以包含 Caption 屬性。 BorderStyle如果衍生自 FormView 的控件屬性是 NotSet 或 None 值，則會GetDesignTimeHtml在控件周圍繪製藍色虛線框線，使其範圍更可見。 此範例不會變更 控件的運行時間外觀。

// Generate the design-time markup.
const string capTag = "caption";
const string trOpen = "tr><td colspan=9 align=center";
const string trClose = "td></tr";

public override string GetDesignTimeHtml()
{
    // Make the full extent of the control more visible in the designer.
    // If the border style is None or NotSet, change the border to
    // a wide, blue, dashed line. Include the caption within the border.
    MyFormView myGV = (MyFormView)Component;
    string markup = null;
    int charX;

    // Check if the border style should be changed.
    if (myGV.BorderStyle == BorderStyle.NotSet ||
        myGV.BorderStyle == BorderStyle.None)
    {
        BorderStyle oldBorderStyle = myGV.BorderStyle;
        Unit oldBorderWidth = myGV.BorderWidth;
        Color oldBorderColor = myGV.BorderColor;

        // Set the design-time properties and catch any exceptions.
        try
        {
            myGV.BorderStyle = BorderStyle.Dashed;
            myGV.BorderWidth = Unit.Pixel(3);
            myGV.BorderColor = Color.Blue;

            // Call the base method to generate the markup.
            markup = base.GetDesignTimeHtml();
        }
        catch (Exception ex)
        {
            markup = GetErrorDesignTimeHtml(ex);
        }
        finally
        {
            // Restore the properties to their original settings.
            myGV.BorderStyle = oldBorderStyle;
            myGV.BorderWidth = oldBorderWidth;
            myGV.BorderColor = oldBorderColor;
        }
    }
    else
    {
        // Call the base method to generate the markup.
        markup = base.GetDesignTimeHtml();
    }

    // Look for a <caption> tag.
    if ((charX = markup.IndexOf(capTag)) > 0)
    {
        // Replace the first caption with 
        // "tr><td colspan=9 align=center".
        // It is okay if the colspan exceeds the 
        // number of columns in the table.
        markup = markup.Remove(charX,
            capTag.Length).Insert(charX, trOpen);

        // Replace the second caption with "td></tr".
        if ((charX = markup.IndexOf(capTag, charX)) > 0)
            markup = markup.Remove(charX,
                capTag.Length).Insert(charX, trClose);
    }
    return markup;
} // GetDesignTimeHtml

' Generate the design-time markup.
Private Const capTag As String = "caption"
Private Const trOpen As String = "tr><td colspan=9 align=center"
Private Const trClose As String = "td></tr"

Public Overrides Function GetDesignTimeHtml() As String

    ' Make the full extent of the control more visible in the designer.
    ' If the border style is None or NotSet, change the border to
    ' a wide, blue, dashed line. Include the caption within the border.
    Dim myGV As MyFormView = CType(Component, MyFormView)
    Dim markup As String = Nothing
    Dim charX As Integer

    ' Check if the border style should be changed.
    If (myGV.BorderStyle = BorderStyle.NotSet Or _
        myGV.BorderStyle = BorderStyle.None) Then

        Dim oldBorderStyle As BorderStyle = myGV.BorderStyle
        Dim oldBorderWidth As Unit = myGV.BorderWidth
        Dim oldBorderColor As Color = myGV.BorderColor

        ' Set the design-time properties and catch any exceptions.
        Try
            myGV.BorderStyle = BorderStyle.Dashed
            myGV.BorderWidth = Unit.Pixel(3)
            myGV.BorderColor = Color.Blue

            ' Call the base method to generate the markup.
            markup = MyBase.GetDesignTimeHtml()

        Catch ex As Exception
            markup = GetErrorDesignTimeHtml(ex)

        Finally
            ' Restore the properties to their original settings.
            myGV.BorderStyle = oldBorderStyle
            myGV.BorderWidth = oldBorderWidth
            myGV.BorderColor = oldBorderColor
        End Try

    Else
        ' Call the base method to generate the markup.
        markup = MyBase.GetDesignTimeHtml()
    End If

    ' Look for a <caption> tag.
    charX = markup.IndexOf(capTag)
    If charX > 0 Then

        ' Replace the first caption with 
        ' "tr><td colspan=9 align=center".
        ' It is okay if the colspan exceeds the 
        ' number of columns in the table.
        markup = markup.Remove(charX, _
            capTag.Length).Insert(charX, trOpen)

        ' Replace the second caption with "td></tr".
        charX = markup.IndexOf(capTag, charX)
        If charX > 0 Then
            markup = markup.Remove(charX, _
                capTag.Length).Insert(charX, trClose)
        End If
    End If

    Return markup

End Function ' GetDesignTimeHtml

備註

如果已經為 FormView 控件定義專案範本，如果無法取得數據源的架構， GetDesignTimeHtml 方法會將控件的集合設定 DataKeyNames 為空 String 數位列。 會 GetDesignTimeHtml 重新整理 TypeDescriptor 對象，強制呼叫 PreFilterProperties 方法。 GetDesignTimeHtml接著會呼叫基底方法來產生標記。

如果控件未定義 FormView 任何項目範本，則會 GetDesignTimeHtml 呼叫 GetEmptyDesignTimeHtml 方法來產生呈現至佔位元的標記。

給繼承者的注意事項

如果您覆寫 GetDesignTimeHtml() 方法，請務必呼叫基底方法，因為它最終會透過數個覆寫層級、在控件上 FormView 呼叫 或控件的 FormView 複本來產生標記。

適用於

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