Style.BackColor Vlastnost
Definice
Důležité
Některé informace platí pro předběžně vydaný produkt, který se může zásadně změnit, než ho výrobce nebo autor vydá. Microsoft neposkytuje žádné záruky, výslovné ani předpokládané, týkající se zde uváděných informací.
Získá nebo nastaví barvu pozadí ovládacího prvku webového serveru.
public:
property System::Drawing::Color BackColor { System::Drawing::Color get(); void set(System::Drawing::Color value); };[System.ComponentModel.Bindable(true)]
[System.ComponentModel.TypeConverter(typeof(System.Web.UI.WebControls.WebColorConverter))]
public System.Drawing.Color BackColor { get; set; }[System.ComponentModel.TypeConverter(typeof(System.Web.UI.WebControls.WebColorConverter))]
public System.Drawing.Color BackColor { get; set; }[<System.ComponentModel.Bindable(true)>]
[<System.ComponentModel.TypeConverter(typeof(System.Web.UI.WebControls.WebColorConverter))>]
member this.BackColor : System.Drawing.Color with get, set[<System.ComponentModel.TypeConverter(typeof(System.Web.UI.WebControls.WebColorConverter))>]
member this.BackColor : System.Drawing.Color with get, setPublic Property BackColor As ColorHodnota vlastnosti
A Color , která představuje barvu pozadí ovládacího prvku. Výchozí hodnota je Empty, což znamená, že tato vlastnost není nastavená.
- Atributy
Příklady
Tento příklad ukazuje, jak pomocí objektu Style změnit vlastnosti stylu více ovládacích prvků najednou. Pokaždé, když se Style změní jedna z hodnot vlastností, musí každý ovládací prvek volat svou ApplyStyle metodu. Všimněte si, že ne všechny ovládací prvky podporují všechny uvedené vlastnosti. Pokud ovládací prvek nepodporuje konkrétní vlastnost, vzhled ovládacího prvku se při změně hodnoty vlastnosti nezmění.
Poznámka
Následující ukázka kódu používá model s jedním souborem kódu a nemusí správně fungovat, pokud je zkopírován přímo do souboru s kódem na pozadí. Tento vzorový kód musí být zkopírován do prázdného textového souboru s příponou .aspx. Další informace o modelu kódu webových formulářů najdete v tématu ASP.NET model kódu stránky webových formulářů.
<!-- -->
<!-- -->
<%@ Page Language="C#" %>
<%@ Import Namespace="System.Drawing" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
private Style primaryStyle = new Style();
void Page_Load(object sender, System.EventArgs e)
{
if (!Page.IsPostBack)
{
// Add data to the borderColorList,
// backColorList, and foreColorList controls.
ListItemCollection colors = new ListItemCollection();
colors.Add(Color.Black.Name);
colors.Add(Color.Blue.Name);
colors.Add(Color.Green.Name);
colors.Add(Color.Orange.Name);
colors.Add(Color.Purple.Name);
colors.Add(Color.Red.Name);
colors.Add(Color.White.Name);
colors.Add(Color.Yellow.Name);
borderColorList.DataSource = colors;
borderColorList.DataBind();
backColorList.DataSource = colors;
backColorList.DataBind();
foreColorList.DataSource = colors;
foreColorList.DataBind();
//<Snippet4>
// Add data to the borderStyleList control.
ListItemCollection styles = new ListItemCollection();
Type styleType = typeof(BorderStyle);
foreach (string s in Enum.GetNames(styleType))
{
styles.Add(s);
}
borderStyleList.DataSource = styles;
borderStyleList.DataBind();
//</Snippet4>
// Add data to the borderWidthList control.
ListItemCollection widths = new ListItemCollection();
for (int i = 0; i < 11; i++)
{
widths.Add(i.ToString() + "px");
}
borderWidthList.DataSource = widths;
borderWidthList.DataBind();
// Add data to the fontNameList control.
ListItemCollection names = new ListItemCollection();
names.Add("Arial");
names.Add("Courier");
names.Add("Garamond");
names.Add("Times New Roman");
names.Add("Verdana");
fontNameList.DataSource = names;
fontNameList.DataBind();
// Add data to the fontSizeList control.
ListItemCollection fontSizes = new ListItemCollection();
fontSizes.Add("Small");
fontSizes.Add("Medium");
fontSizes.Add("Large");
fontSizes.Add("10pt");
fontSizes.Add("14pt");
fontSizes.Add("20pt");
fontSizeList.DataSource = fontSizes;
fontSizeList.DataBind();
//Set primaryStyle as the style for each control.
Label1.ApplyStyle(primaryStyle);
ListBox1.ApplyStyle(primaryStyle);
Button1.ApplyStyle(primaryStyle);
Table1.ApplyStyle(primaryStyle);
TextBox1.ApplyStyle(primaryStyle);
}
}
//<Snippet5>
void ChangeBorderColor(object sender, System.EventArgs e)
{
primaryStyle.BorderColor =
Color.FromName(borderColorList.SelectedItem.Text);
Label1.ApplyStyle(primaryStyle);
ListBox1.ApplyStyle(primaryStyle);
Button1.ApplyStyle(primaryStyle);
Table1.ApplyStyle(primaryStyle);
TextBox1.ApplyStyle(primaryStyle);
}
//</Snippet5>
//<Snippet6>
void ChangeBackColor(object sender, System.EventArgs e)
{
primaryStyle.BackColor =
Color.FromName(backColorList.SelectedItem.Text);
Label1.ApplyStyle(primaryStyle);
ListBox1.ApplyStyle(primaryStyle);
Button1.ApplyStyle(primaryStyle);
Table1.ApplyStyle(primaryStyle);
TextBox1.ApplyStyle(primaryStyle);
}
//</Snippet6>
//<Snippet7>
void ChangeForeColor(object sender, System.EventArgs e)
{
primaryStyle.ForeColor =
Color.FromName(foreColorList.SelectedItem.Text);
Label1.ApplyStyle(primaryStyle);
ListBox1.ApplyStyle(primaryStyle);
Button1.ApplyStyle(primaryStyle);
Table1.ApplyStyle(primaryStyle);
TextBox1.ApplyStyle(primaryStyle);
}
//</Snippet7>
//<Snippet8>
void ChangeBorderStyle(object sender, System.EventArgs e)
{
primaryStyle.BorderStyle =
(BorderStyle)Enum.Parse(typeof(BorderStyle),
borderStyleList.SelectedItem.Text);
Label1.ApplyStyle(primaryStyle);
ListBox1.ApplyStyle(primaryStyle);
Button1.ApplyStyle(primaryStyle);
Table1.ApplyStyle(primaryStyle);
TextBox1.ApplyStyle(primaryStyle);
}
//</Snippet8>
//<Snippet9>
void ChangeBorderWidth(object sender, System.EventArgs e)
{
primaryStyle.BorderWidth =
Unit.Parse(borderWidthList.SelectedItem.Text);
Label1.ApplyStyle(primaryStyle);
ListBox1.ApplyStyle(primaryStyle);
Button1.ApplyStyle(primaryStyle);
Table1.ApplyStyle(primaryStyle);
TextBox1.ApplyStyle(primaryStyle);
}
//</Snippet9>
//<Snippet10>
void ChangeFont(object sender, System.EventArgs e)
{
primaryStyle.Font.Name =
fontNameList.SelectedItem.Text;
Label1.ApplyStyle(primaryStyle);
ListBox1.ApplyStyle(primaryStyle);
Button1.ApplyStyle(primaryStyle);
Table1.ApplyStyle(primaryStyle);
TextBox1.ApplyStyle(primaryStyle);
}
//</Snippet10>
//<Snippet11>
void ChangeFontSize(object sender, System.EventArgs e)
{
primaryStyle.Font.Size =
FontUnit.Parse(fontSizeList.SelectedItem.Text);
Label1.ApplyStyle(primaryStyle);
ListBox1.ApplyStyle(primaryStyle);
Button1.ApplyStyle(primaryStyle);
Table1.ApplyStyle(primaryStyle);
TextBox1.ApplyStyle(primaryStyle);
}
//</Snippet11>
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>Untitled Page</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<table cellpadding="6" border="0">
<tr>
<td rowspan="10" style="border:solid 1px Gray">
<p>
<asp:label id="Label1"
Text="Border Properties Example" Runat="server">
Label Styles
</asp:label>
</p>
<p>
<asp:button id="Button1" runat="server"
Text="Button Styles">
</asp:button>
</p>
<p>
<asp:listbox id="ListBox1" Runat="server">
<asp:ListItem Value="0" Text="List Item 0">
</asp:ListItem>
<asp:ListItem Value="1" Text="List Item 1">
</asp:ListItem>
<asp:ListItem Value="2" Text="List Item 2">
</asp:ListItem>
</asp:listbox>
</p>
<p>
<asp:textbox id="TextBox1"
Text="TextBox Styles" Runat="server">
</asp:textbox>
</p>
<p>
<asp:table id="Table1" Runat="server">
<asp:TableRow>
<asp:TableCell Text="(0,0)"></asp:TableCell>
<asp:TableCell Text="(0,1)"></asp:TableCell>
</asp:TableRow>
<asp:TableRow>
<asp:TableCell Text="(1,0)"></asp:TableCell>
<asp:TableCell Text="(1,1)"></asp:TableCell>
</asp:TableRow>
</asp:table>
</p>
</td>
<td align="right">
<asp:Label ID="Label2" runat="server"
AssociatedControlID="borderColorList"
Text="Border Color:">
</asp:Label>
</td>
<td>
<asp:dropdownlist id="borderColorList"
Runat="server" AutoPostBack="True"
OnSelectedIndexChanged="ChangeBorderColor">
</asp:dropdownlist>
</td>
</tr>
<tr>
<td align="right">
<asp:Label ID="Label3" Runat="server"
AssociatedControlID="borderStyleList"
Text="Border Style:">
</asp:Label>
</td>
<td>
<asp:dropdownlist id="borderStyleList"
Runat="server" AutoPostBack="True"
OnSelectedIndexChanged="ChangeBorderStyle">
</asp:dropdownlist>
</td>
</tr>
<tr>
<td align="right">
<asp:Label ID="Label4" Runat="server"
AssociatedControlID="borderWidthList"
Text="Border Width">
</asp:Label>
</td>
<td>
<asp:dropdownlist id="borderWidthList"
Runat="server" AutoPostBack="True"
OnSelectedIndexChanged="ChangeBorderWidth">
</asp:dropdownlist>
</td>
</tr>
<tr>
<td align="right">
<asp:Label ID="Label5" Runat="server"
AssociatedControlID="backColorList"
Text="Back Color:">
</asp:Label>
</td>
<td>
<asp:dropdownlist id="backColorList"
Runat="server" AutoPostBack="True"
OnSelectedIndexChanged="ChangeBackColor">
</asp:dropdownlist>
</td>
</tr>
<tr>
<td align="right">
<asp:Label ID="Label6" Runat="server"
AssociatedControlID="foreColorList"
Text="Foreground Color:">
</asp:Label>
</td>
<td>
<asp:dropdownlist id="foreColorList"
Runat="server" AutoPostBack="True"
OnSelectedIndexChanged="ChangeForeColor">
</asp:dropdownlist>
</td>
</tr>
<tr>
<td align="right">
<asp:Label ID="Label7" Runat="server"
AssociatedControlID="fontNameList"
Text="Font Name:">
</asp:Label>
</td>
<td>
<asp:dropdownlist id="fontNameList"
Runat="server" AutoPostBack="True"
OnSelectedIndexChanged="ChangeFont">
</asp:dropdownlist>
</td>
</tr>
<tr>
<td align="right">
<asp:Label ID="Label8" Runat="server"
AssociatedControlID="fontSizeList"
Text="Font Size:">
</asp:Label>
</td>
<td>
<asp:dropdownlist id="fontSizeList"
Runat="server" AutoPostBack="True"
OnSelectedIndexChanged="ChangeFontSize">
</asp:dropdownlist>
</td>
</tr>
</table>
</div>
</form>
</body>
</html>
<%@ Page Language="VB" %>
<%@ Import Namespace="System.Drawing" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
Private primaryStyle As New Style()
Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs)
If Not Page.IsPostBack Then
' Add data to the borderColorList,
' backColorList, and foreColorList controls.
Dim colors As New ListItemCollection()
colors.Add(Color.Black.Name)
colors.Add(Color.Blue.Name)
colors.Add(Color.Green.Name)
colors.Add(Color.Orange.Name)
colors.Add(Color.Purple.Name)
colors.Add(Color.Red.Name)
colors.Add(Color.White.Name)
colors.Add(Color.Yellow.Name)
borderColorList.DataSource = colors
borderColorList.DataBind()
backColorList.DataSource = colors
backColorList.DataBind()
foreColorList.DataSource = colors
foreColorList.DataBind()
'<Snippet4>
' Add data to the borderStyleList control.
Dim styles As New ListItemCollection()
Dim styleType As Type = GetType(BorderStyle)
Dim s As String
For Each s In [Enum].GetNames(styleType)
styles.Add(s)
Next s
borderStyleList.DataSource = styles
borderStyleList.DataBind()
'</Snippet4>
' Add data to the borderWidthList control.
Dim widths As New ListItemCollection()
Dim i As Integer
For i = 0 To 10
widths.Add(i.ToString() & "px")
Next i
borderWidthList.DataSource = widths
borderWidthList.DataBind()
' Add data to the fontNameList control.
Dim names As New ListItemCollection()
names.Add("Arial")
names.Add("Courier")
names.Add("Garamond")
names.Add("Times New Roman")
names.Add("Verdana")
fontNameList.DataSource = names
fontNameList.DataBind()
' Add data to the fontSizeList control.
Dim fontSizes As New ListItemCollection()
fontSizes.Add("Small")
fontSizes.Add("Medium")
fontSizes.Add("Large")
fontSizes.Add("10pt")
fontSizes.Add("14pt")
fontSizes.Add("20pt")
fontSizeList.DataSource = fontSizes
fontSizeList.DataBind()
' Set primaryStyle as the style for each control.
Label1.ApplyStyle(primaryStyle)
ListBox1.ApplyStyle(primaryStyle)
Button1.ApplyStyle(primaryStyle)
Table1.ApplyStyle(primaryStyle)
TextBox1.ApplyStyle(primaryStyle)
End If
End Sub
'<Snippet5>
Sub ChangeBorderColor(ByVal sender As Object, ByVal e As System.EventArgs)
primaryStyle.BorderColor = _
Color.FromName(borderColorList.SelectedItem.Text)
Label1.ApplyStyle(primaryStyle)
ListBox1.ApplyStyle(primaryStyle)
Button1.ApplyStyle(primaryStyle)
Table1.ApplyStyle(primaryStyle)
TextBox1.ApplyStyle(primaryStyle)
End Sub
'</Snippet5>
'<Snippet6>
Sub ChangeBackColor(ByVal sender As Object, ByVal e As System.EventArgs)
primaryStyle.BackColor = _
Color.FromName(backColorList.SelectedItem.Text)
Label1.ApplyStyle(primaryStyle)
ListBox1.ApplyStyle(primaryStyle)
Button1.ApplyStyle(primaryStyle)
Table1.ApplyStyle(primaryStyle)
TextBox1.ApplyStyle(primaryStyle)
End Sub
'</Snippet6>
'<Snippet7>
Sub ChangeForeColor(ByVal sender As Object, ByVal e As System.EventArgs)
primaryStyle.ForeColor = _
Color.FromName(foreColorList.SelectedItem.Text)
Label1.ApplyStyle(primaryStyle)
ListBox1.ApplyStyle(primaryStyle)
Button1.ApplyStyle(primaryStyle)
Table1.ApplyStyle(primaryStyle)
TextBox1.ApplyStyle(primaryStyle)
End Sub
'</Snippet7>
'<Snippet8>
Sub ChangeBorderStyle(ByVal sender As Object, ByVal e As System.EventArgs)
primaryStyle.BorderStyle = _
CType([Enum].Parse(GetType(BorderStyle), _
borderStyleList.SelectedItem.Text), BorderStyle)
Label1.ApplyStyle(primaryStyle)
ListBox1.ApplyStyle(primaryStyle)
Button1.ApplyStyle(primaryStyle)
Table1.ApplyStyle(primaryStyle)
TextBox1.ApplyStyle(primaryStyle)
End Sub
'</Snippet8>
'<Snippet9>
Sub ChangeBorderWidth(ByVal sender As Object, ByVal e As System.EventArgs)
primaryStyle.BorderWidth = _
Unit.Parse(borderWidthList.SelectedItem.Text)
Label1.ApplyStyle(primaryStyle)
ListBox1.ApplyStyle(primaryStyle)
Button1.ApplyStyle(primaryStyle)
Table1.ApplyStyle(primaryStyle)
TextBox1.ApplyStyle(primaryStyle)
End Sub
'</Snippet9>
'<Snippet10>
Sub ChangeFont(ByVal sender As Object, ByVal e As System.EventArgs)
primaryStyle.Font.Name = _
fontNameList.SelectedItem.Text
Label1.ApplyStyle(primaryStyle)
ListBox1.ApplyStyle(primaryStyle)
Button1.ApplyStyle(primaryStyle)
Table1.ApplyStyle(primaryStyle)
TextBox1.ApplyStyle(primaryStyle)
End Sub
'</Snippet10>
'<Snippet11>
Sub ChangeFontSize(ByVal sender As Object, ByVal e As System.EventArgs)
primaryStyle.Font.Size = _
FontUnit.Parse(fontSizeList.SelectedItem.Text)
Label1.ApplyStyle(primaryStyle)
ListBox1.ApplyStyle(primaryStyle)
Button1.ApplyStyle(primaryStyle)
Table1.ApplyStyle(primaryStyle)
TextBox1.ApplyStyle(primaryStyle)
End Sub
'</Snippet11>
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>Applied Style Example</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<table cellpadding="6" border="0">
<tr>
<td rowspan="10" style="border:solid 1px Gray">
<p>
<asp:label id="Label1"
Text="Border Properties Example" Runat="server">
Label Styles
</asp:label>
</p>
<p>
<asp:button id="Button1" runat="server"
Text="Button Styles">
</asp:button>
</p>
<p>
<asp:listbox id="ListBox1" Runat="server">
<asp:ListItem Value="0" Text="List Item 0">
</asp:ListItem>
<asp:ListItem Value="1" Text="List Item 1">
</asp:ListItem>
<asp:ListItem Value="2" Text="List Item 2">
</asp:ListItem>
</asp:listbox>
</p>
<p>
<asp:textbox id="TextBox1"
Text="TextBox Styles" Runat="server">
</asp:textbox>
</p>
<p>
<asp:table id="Table1" Runat="server">
<asp:TableRow>
<asp:TableCell Text="(0,0)"></asp:TableCell>
<asp:TableCell Text="(0,1)"></asp:TableCell>
</asp:TableRow>
<asp:TableRow>
<asp:TableCell Text="(1,0)"></asp:TableCell>
<asp:TableCell Text="(1,1)"></asp:TableCell>
</asp:TableRow>
</asp:table>
</p>
</td>
<td align="right">
<asp:Label ID="Label2" runat="server"
AssociatedControlID="borderColorList"
Text="Border Color:">
</asp:Label>
</td>
<td>
<asp:dropdownlist id="borderColorList"
Runat="server" AutoPostBack="True"
OnSelectedIndexChanged="ChangeBorderColor">
</asp:dropdownlist>
</td>
</tr>
<tr>
<td align="right">
<asp:Label ID="Label3" Runat="server"
AssociatedControlID="borderStyleList"
Text="Border Style:">
</asp:Label>
</td>
<td>
<asp:dropdownlist id="borderStyleList"
Runat="server" AutoPostBack="True"
OnSelectedIndexChanged="ChangeBorderStyle">
</asp:dropdownlist>
</td>
</tr>
<tr>
<td align="right">
<asp:Label ID="Label4" Runat="server"
AssociatedControlID="borderWidthList"
Text="Border Width">
</asp:Label>
</td>
<td>
<asp:dropdownlist id="borderWidthList"
Runat="server" AutoPostBack="True"
OnSelectedIndexChanged="ChangeBorderWidth">
</asp:dropdownlist>
</td>
</tr>
<tr>
<td align="right">
<asp:Label ID="Label5" Runat="server"
AssociatedControlID="backColorList"
Text="Back Color:">
</asp:Label>
</td>
<td>
<asp:dropdownlist id="backColorList"
Runat="server" AutoPostBack="True"
OnSelectedIndexChanged="ChangeBackColor">
</asp:dropdownlist>
</td>
</tr>
<tr>
<td align="right">
<asp:Label ID="Label6" Runat="server"
AssociatedControlID="foreColorList"
Text="Foreground Color:">
</asp:Label>
</td>
<td>
<asp:dropdownlist id="foreColorList"
Runat="server" AutoPostBack="True"
OnSelectedIndexChanged="ChangeForeColor">
</asp:dropdownlist>
</td>
</tr>
<tr>
<td align="right">
<asp:Label ID="Label7" Runat="server"
AssociatedControlID="fontNameList"
Text="Font Name:">
</asp:Label>
</td>
<td>
<asp:dropdownlist id="fontNameList"
Runat="server" AutoPostBack="True"
OnSelectedIndexChanged="ChangeFont">
</asp:dropdownlist>
</td>
</tr>
<tr>
<td align="right">
<asp:Label ID="Label8" Runat="server"
AssociatedControlID="fontSizeList"
Text="Font Size:">
</asp:Label>
</td>
<td>
<asp:dropdownlist id="fontSizeList"
Runat="server" AutoPostBack="True"
OnSelectedIndexChanged="ChangeFontSize">
</asp:dropdownlist>
</td>
</tr>
</table>
</div>
</form>
</body>
</html>
Poznámky
BackColor Pomocí vlastnosti určete barvu pozadí ovládacího prvku webového serveru. Tato vlastnost je nastavena pomocí objektu System.Drawing.Color .
Poznámka
Tato vlastnost se vykreslí jenom pro určité ovládací prvky. Například Table, , Panel, DataGridCalendara vykreslí ValidationSummary tuto vlastnost. Bude fungovat také pro , a pokud je RepeatLayout.Tablejejich RepeatLayout vlastnost , a ne RepeatLayout.Flow.DataListRadioButtonListCheckBoxList
Obecně platí, že pouze ovládací prvky, které se vykreslují jako <table> značka, mohou zobrazit barvu pozadí v HTML 3.2, zatímco téměř jakýkoli ovládací prvek může v HTML 4.0.
U ovládacích prvků, které se vykreslují jako <span> značka (včetně Label, všech ověřovacích ovládacích prvků a ovládacích prvků seznamu s RepeatLayout vlastností nastavenou na RepeatLayout.Flow), bude tato vlastnost fungovat v aplikaci Microsoft Internet Explorer verze 5 nebo novější, ale ne v aplikaci Microsoft Internet Explorer verze 4.
Platí pro
Viz také
Spolupracujte s námi na GitHubu
Zdroj tohoto obsahu najdete na GitHubu, kde můžete také vytvářet a kontrolovat problémy a žádosti o přijetí změn. Další informace najdete v našem průvodci pro přispěvatele.
