ImageField.ReadOnly 屬性
定義
重要
部分資訊涉及發行前產品,在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊,不做任何明確或隱含的瑕疵擔保。
取得或設定值,表示是否可以在編輯模式下修改 DataImageUrlField 屬性所指定的欄位值。
public:
virtual property bool ReadOnly { bool get(); void set(bool value); };
public virtual bool ReadOnly { get; set; }
member this.ReadOnly : bool with get, set
Public Overridable Property ReadOnly As Boolean
屬性值
true
表示在編輯模式下無法修改欄位值,否則為 false
。 預設為 false
。
範例
下列範例示範如何使用 ReadOnly 屬性來指出代表物件中所 ImageField 顯示影像的域值無法在編輯模式中修改。
<%@ Page language="C#" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>ImageField ReadOnly Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>ImageField ReadOnly Example</h3>
<asp:gridview id="EmployeesGrid"
autogeneratecolumns="false"
datasourceid="EmployeeSource"
autogenerateeditbutton="true"
datakeynames="EmployeeID"
runat="server">
<columns>
<asp:imagefield dataimageurlfield="PhotoPath"
alternatetext="Employee Photo"
nulldisplaytext="No image on file."
headertext="Photo"
readonly="true"/>
<asp:boundfield datafield="FirstName"
headertext="First Name"/>
<asp:boundfield datafield="LastName"
headertext="Last Name"/>
</columns>
</asp:gridview>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the Northwind sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the Web.config file. -->
<asp:sqldatasource id="EmployeeSource"
selectcommand="Select [EmployeeID], [LastName], [FirstName], [PhotoPath] From [Employees]"
updatecommand="Update [Employees] Set [LastName]=@LastName, [FirstName]=@FirstName Where [EmployeeId]=@EmployeeID"
connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</form>
</body>
</html>
<%@ Page language="VB" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>ImageField ReadOnly Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>ImageField ReadOnly Example</h3>
<asp:gridview id="EmployeesGrid"
autogeneratecolumns="false"
datasourceid="EmployeeSource"
autogenerateeditbutton="true"
datakeynames="EmployeeID"
runat="server">
<columns>
<asp:imagefield dataimageurlfield="PhotoPath"
alternatetext="Employee Photo"
nulldisplaytext="No image on file."
headertext="Photo"
readonly="true"/>
<asp:boundfield datafield="FirstName"
headertext="First Name"/>
<asp:boundfield datafield="LastName"
headertext="Last Name"/>
</columns>
</asp:gridview>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the Northwind sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the Web.config file. -->
<asp:sqldatasource id="EmployeeSource"
selectcommand="Select [EmployeeID], [LastName], [FirstName], [PhotoPath] From [Employees]"
updatecommand="Update [Employees] Set [LastName]=@LastName, [FirstName]=@FirstName Where [EmployeeId]=@EmployeeID"
connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</form>
</body>
</html>
備註
根據預設,當資料繫結控制項處於編輯模式時,使用者可以修改屬性所 DataImageUrlField 指定的域值。 若要防止使用者變更欄位的值,請將此屬性設定為 true
。
注意
ImageField在 物件中 DataImageUrlField ,屬性通常包含功能變數名稱,其中包含物件中所顯示影像的 URL。