FormParameter 构造函数

参考

定义

命名空间:: System.Web.UI.WebControls

程序集:: System.Web.dll

重要

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初始化 FormParameter 类的新实例。

重载

FormParameter()	初始化 FormParameter 类的未命名新实例。
FormParameter(FormParameter)	使用 `original` 参数指定的实例的值初始化 FormParameter 类的新实例。
FormParameter(String, String)	使用指定字符串标识要绑定到的窗体变量字段，初始化 FormParameter 类的一个新的已命名的实例。
FormParameter(String, DbType, String)	通过使用指定的字符串标识要绑定到的窗体变量字段，初始化 FormParameter 类的新实例。
FormParameter(String, TypeCode, String)	使用指定字符串标识要绑定到的窗体变量，初始化 FormParameter 类的一个新的已命名的强类型实例。

FormParameter()

初始化 FormParameter 类的未命名新实例。

public:
 FormParameter();

public FormParameter ();

Public Sub New ()

示例

重要

FormParameter不会以任何方式验证 form 元素传递的值;它使用原始值。在大多数情况下，可以通过处理事件（例如 InsertingSelectingUpdating，、、或 Deleting 所使用的数据源控件公开的事件），在数据源控件使用它之前验证 FormParameter 的值。如果参数的值未通过验证测试，可以通过将关联CancelEventArgs类的属性设置为 Canceltrue来取消数据操作。

<%@Page  Language="C#" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">

void Page_Load(Object sender, EventArgs e){

  // You can add a FormParameter to the AccessDataSource control's
  // SelectParameters collection programmatically.
  AccessDataSource1.SelectParameters.Clear();

  // Security Note: The AccessDataSource uses a FormParameter,
  // Security Note: which does not perform validation of input from the client.
  // Security Note: To validate the value of the FormParameter,
  // Security Note: handle the Selecting event.

  FormParameter formParam = new FormParameter();
  formParam.Name="lastname";
  formParam.Type=TypeCode.String;
  formParam.FormField="LastNameBox";
  AccessDataSource1.SelectParameters.Add(formParam);
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>ASP.NET Example</title>
</head>
<body>
    <form id="form1" runat="server">

      <asp:accessdatasource
          id="AccessDataSource1"
          runat="server"
          datasourcemode="DataSet"
          datafile="Northwind.mdb"
          selectcommand="SELECT OrderID,CustomerID,OrderDate,RequiredDate,ShippedDate
                         FROM Orders WHERE EmployeeID =
                         (SELECT EmployeeID FROM Employees WHERE LastName = @lastname)">
      </asp:accessdatasource>

      <br />Enter the name "Davolio" or "King" in the text box and click the button.

      <br />
      <asp:textbox
        id="LastNameBox"
        runat="server" />

      <br />
      <asp:button
        id="Button1"
        runat="server"
        text="Get Records" />

      <br />
      <asp:gridview
          id="GridView1"
          runat="server"
          allowsorting="True"
          datasourceid="AccessDataSource1" />

    </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">

<script runat="server">

Private Sub Page_Load(sender As Object, e As EventArgs)

  ' You can add a FormParameter to the AccessDataSource control's
  ' SelectParameters collection programmatically.
  AccessDataSource1.SelectParameters.Clear()

  ' Security Note: The AccessDataSource uses a FormParameter,
  ' Security Note: which does not perform validation of input from the client.
  ' Security Note: To validate the value of the FormParameter,
  ' Security Note: handle the Selecting event.
  Dim formParam As New FormParameter()
  formParam.Name="lastname"
  formParam.Type=TypeCode.String
  formParam.FormField="LastNameBox"
  AccessDataSource1.SelectParameters.Add(formParam)

End Sub ' Page_Load

</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>ASP.NET Example</title>
</head>
<body>
    <form id="form1" runat="server">

      <asp:accessdatasource
          id="AccessDataSource1"
          runat="server"
          datasourcemode="DataSet"
          datafile="Northwind.mdb"
          selectcommand="SELECT OrderID,CustomerID,OrderDate,RequiredDate,ShippedDate
                         FROM Orders WHERE EmployeeID =
                         (SELECT EmployeeID FROM Employees WHERE LastName = @lastname)">
      </asp:accessdatasource>

      <br />Enter the name "Davolio" or "King" in the text box and click the button.

      <br />
      <asp:textbox
        id="LastNameBox"
        runat="server" />

      <br />
      <asp:button
        id="Button1"
        runat="server"
        text="Get Records" />

      <br />
      <asp:gridview
          id="GridView1"
          runat="server"
          allowsorting="True"
          datasourceid="AccessDataSource1" />

    </form>
  </body>
</html>

注解

FormParameter使用 FormParameter 构造函数创建的对象使用其所有属性的默认值进行初始化。初始化 FormField 为 String.Empty。此外，属性 Name 初始化为 String.Empty， Type 属性初始化为 TypeCode.Object， Direction 属性初始化为，属性初始化为 Input，属性 DefaultValue 初始化为 visual Basic) 中的 null (Nothing 。

另请参阅

对数据源控件使用参数

适用于

FormParameter(FormParameter)

使用 original 参数指定的实例的值初始化 FormParameter 类的新实例。

protected:
 FormParameter(System::Web::UI::WebControls::FormParameter ^ original);

protected FormParameter (System.Web.UI.WebControls.FormParameter original);

new System.Web.UI.WebControls.FormParameter : System.Web.UI.WebControls.FormParameter -> System.Web.UI.WebControls.FormParameter

Protected Sub New (original As FormParameter)

参数

original: FormParameter

一个 FormParameter 实例，将从该实例初始化当前实例。

注解

构造 FormParameter 函数是 protected 用于克隆实例的 FormParameter 复制构造函数。、（包括 FormField、 Name和 Type ）的值FormParameter全部传输到新实例。

另请参阅

适用于

FormParameter(String, String)

使用指定字符串标识要绑定到的窗体变量字段，初始化 FormParameter 类的一个新的已命名的实例。

public:
 FormParameter(System::String ^ name, System::String ^ formField);

public FormParameter (string name, string formField);

new System.Web.UI.WebControls.FormParameter : string * string -> System.Web.UI.WebControls.FormParameter

Public Sub New (name As String, formField As String)

参数

name: String

参数的名称。

formField: String

将参数对象绑定到的窗体变量的名称。默认值为 Empty。

示例

重要

<%@Page  Language="C#" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">

void Page_Load(Object sender, EventArgs e){

  // You can add a FormParameter to the AccessDataSource control's
  // SelectParameters collection programmatically.
  AccessDataSource1.SelectParameters.Clear();

  // Security Note: The AccessDataSource uses a FormParameter,
  // Security Note: which does not perform validation of input from the client.
  // Security Note: To validate the value of the FormParameter,
  // Security Note: handle the Selecting event.

  FormParameter formParam = new FormParameter("lastname","LastNameBox");
  formParam.Type=TypeCode.String;
  AccessDataSource1.SelectParameters.Add(formParam);
}

</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>ASP.NET Example</title>
</head>
<body>
    <form id="form1" runat="server">

      <asp:accessdatasource
          id="AccessDataSource1"
          runat="server"
          datasourcemode="DataSet"
          datafile="Northwind.mdb"
          selectcommand="SELECT OrderID,CustomerID,OrderDate,RequiredDate,ShippedDate
                         FROM Orders WHERE EmployeeID =
                         (SELECT EmployeeID FROM Employees WHERE LastName = @lastname)">
      </asp:accessdatasource>

      <br />Enter the name "Davolio" or "King" in the text box and click the button.

      <br />
      <asp:textbox
        id="LastNameBox"
        runat="server" />

      <br />
      <asp:button
        id="Button1"
        runat="server"
        text="Get Records" />

      <br />
      <asp:gridview
          id="GridView1"
          runat="server"
          allowsorting="True"
          datasourceid="AccessDataSource1">
      </asp:gridview>

    </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">

<script runat="server">

Private Sub Page_Load(sender As Object, e As EventArgs)

  ' You can add a FormParameter to the AccessDataSource control's
  ' SelectParameters collection programmatically.
  AccessDataSource1.SelectParameters.Clear()

  ' Security Note: The AccessDataSource uses a FormParameter,
  ' Security Note: which does not perform validation of input from the client.
  ' Security Note: To validate the value of the FormParameter,
  ' Security Note: handle the Selecting event.

  Dim formParam As New FormParameter("lastname","LastNameBox")
  formParam.Type=TypeCode.String
  AccessDataSource1.SelectParameters.Add(formParam)
End Sub ' Page_Load

</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>ASP.NET Example</title>
</head>
<body>
    <form id="form1" runat="server">

      <asp:accessdatasource
          id="AccessDataSource1"
          runat="server"
          datasourcemode="DataSet"
          datafile="Northwind.mdb"
          selectcommand="SELECT OrderID,CustomerID,OrderDate,RequiredDate,ShippedDate
                         FROM Orders WHERE EmployeeID =
                         (SELECT EmployeeID FROM Employees WHERE LastName = @lastname)">
      </asp:accessdatasource>

      <br />Enter the name "Davolio" or "King" in the text box and click the button.

      <br />
      <asp:textbox
        id="LastNameBox"
        runat="server" />

      <br />
      <asp:button
        id="Button1"
        runat="server"
        text="Get Records" />

      <br />
      <asp:gridview
          id="GridView1"
          runat="server"
          allowsorting="True"
          datasourceid="AccessDataSource1">
      </asp:gridview>

    </form>
  </body>
</html>

注解

FormParameter使用FormParameter构造函数创建的对象使用指定的参数名称和字符串进行初始化，该参数标识该参数绑定到的窗体变量。使用 Type 默认值初始化和 Direction 属性。

另请参阅

适用于

FormParameter(String, DbType, String)

通过使用指定的字符串标识要绑定到的窗体变量字段，初始化 FormParameter 类的新实例。

public:
 FormParameter(System::String ^ name, System::Data::DbType dbType, System::String ^ formField);

public FormParameter (string name, System.Data.DbType dbType, string formField);

new System.Web.UI.WebControls.FormParameter : string * System.Data.DbType * string -> System.Web.UI.WebControls.FormParameter

Public Sub New (name As String, dbType As DbType, formField As String)

参数

name: String

参数的名称。

dbType: DbType

参数的数据库类型。

formField: String

将参数对象绑定到的窗体变量的名称。

适用于

FormParameter(String, TypeCode, String)

使用指定字符串标识要绑定到的窗体变量，初始化 FormParameter 类的一个新的已命名的强类型实例。

public:
 FormParameter(System::String ^ name, TypeCode type, System::String ^ formField);

public FormParameter (string name, TypeCode type, string formField);

new System.Web.UI.WebControls.FormParameter : string * TypeCode * string -> System.Web.UI.WebControls.FormParameter

Public Sub New (name As String, type As TypeCode, formField As String)

参数

name: String

参数的名称。

type: TypeCode

该参数所表示的类型。默认值为 Object。

formField: String

将参数对象绑定到的窗体变量的名称。默认值为 Empty。

示例

重要

<%@Page  Language="C#" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">

void Page_Load(Object sender, EventArgs e){

  // You can add a FormParameter to the AccessDataSource control's
  // SelectParameters collection programmatically.
  AccessDataSource1.SelectParameters.Clear();

  // Security Note: The AccessDataSource uses a FormParameter,
  // Security Note: which does not perform validation of input from the client.
  // Security Note: To validate the value of the FormParameter,
  // Security Note: handle the Selecting event.

  FormParameter formParam = new FormParameter("lastname", TypeCode.String, "LastNameBox");
  AccessDataSource1.SelectParameters.Add(formParam);
}

</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>ASP.NET Example</title>
</head>
<body>
    <form id="form1" runat="server">

      <asp:accessdatasource
          id="AccessDataSource1"
          runat="server"
          datasourcemode="DataSet"
          datafile="Northwind.mdb"
          selectcommand="SELECT OrderID,CustomerID,OrderDate,RequiredDate,ShippedDate
                         FROM Orders WHERE EmployeeID =
                          (SELECT EmployeeID FROM Employees WHERE LastName = @lastname)">
      </asp:accessdatasource>

      <br />Enter the name "Davolio" or "King" in the text box and click the button.

      <br />
      <asp:textbox
        id="LastNameBox"
        runat="server" />

      <br />
      <asp:button
        id="Button1"
        runat="server"
        text="Get Records" />

      <br />
      <asp:gridview
          id="GridView1"
          runat="server"
          allowsorting="True"
          datasourceid="AccessDataSource1">
      </asp:gridview>

    </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">

<script runat="server">

Private Sub Page_Load(sender As Object, e As EventArgs)

  ' You can add a FormParameter to the AccessDataSource control's
  ' SelectParameters collection programmatically.
  AccessDataSource1.SelectParameters.Clear()

  ' Security Note: The AccessDataSource uses a FormParameter,
  ' Security Note: which does not perform validation of input from the client.
  ' Security Note: To validate the value of the FormParameter,
  ' Security Note: handle the Selecting event.

  Dim formParam As New FormParameter("lastname",TypeCode.String,"LastNameBox")
  AccessDataSource1.SelectParameters.Add(formParam)

End Sub ' Page_Load

</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>ASP.NET Example</title>
</head>
<body>
    <form id="form1" runat="server">

      <asp:accessdatasource
          id="AccessDataSource1"
          runat="server"
          datasourcemode="DataSet"
          datafile="Northwind.mdb"
          selectcommand="SELECT OrderID,CustomerID,OrderDate,RequiredDate,ShippedDate
                         FROM Orders WHERE EmployeeID =
                           (SELECT EmployeeID FROM Employees WHERE LastName = @lastname)">
      </asp:accessdatasource>

      <br />Enter the name "Davolio" or "King" in the text box and click the button.

      <br />
      <asp:textbox
        id="LastNameBox"
        runat="server" />

      <br />
      <asp:button
        id="Button1"
        runat="server"
        text="Get Records" />

      <br />
      <asp:gridview
          id="GridView1"
          runat="server"
          allowsorting="True"
          datasourceid="AccessDataSource1">
      </asp:gridview>

    </form>
  </body>
</html>

注解

FormParameter使用 FormParameter 构造函数创建的对象使用指定的参数名称、和字符串进行初始化，Type该字符串标识该参数绑定到的窗体变量。仅使用 Direction 默认值初始化和 ConvertEmptyStringToNull 属性。

另请参阅

适用于

通过

FormParameter 构造函数

定义

重载

FormParameter()

示例

注解

另请参阅

适用于

FormParameter(FormParameter)

参数

注解

另请参阅

适用于

FormParameter(String, String)

参数

示例

注解

另请参阅

适用于

FormParameter(String, DbType, String)

参数

适用于

FormParameter(String, TypeCode, String)

参数

示例

注解

另请参阅

适用于

其他资源