DataObject.GetData 方法

public:
 virtual System::Object ^ GetData(System::String ^ format, bool autoConvert);

public virtual object GetData (string format, bool autoConvert);

public virtual object? GetData (string format, bool autoConvert);

abstract member GetData : string * bool -> obj
override this.GetData : string * bool -> obj

Public Overridable Function GetData (format As String, autoConvert As Boolean) As Object

参数

返回

与指定格式关联的数据，或为 null。

实现

示例

下面的代码示例使用 autoConvert 参数来指定是否转换数据格式，检索存储在 DataObject中的数据。

首先，使用文本数据创建新的 DataObject 。 然后，该示例尝试检索数据，将其格式指定为字符串，并且不进行格式转换，即 参数 autoConvert 为 false。 此操作失败，因为 中 DataObject没有字符串数据。

接下来，该示例尝试再次检索数据，并将 autoConvert 参数设置为 true。 此操作成功，结果显示在 中 MessageBox。

此代码要求 textBox1 已创建 。

private:
   void GetMyData3()
   {
      // Creates a new data object using a string and the text format.
      String^ myString = "My new text string";
      DataObject^ myDataObject = gcnew DataObject( DataFormats::Text,myString );
      
      // Prints the string in a text box with autoconvert = false.
      if ( myDataObject->GetData( "System.String", false ) != 0 )
      {
         // Prints the string in a text box.
         textBox1->Text = String::Concat(
            myDataObject->GetData( "System.String", false )->ToString(), "\n" );
      }
      else
      {
         textBox1->Text = "Could not find data of the specified format\n";
      }
      
      // Prints the string in a text box with autoconvert = true.
      textBox1->Text = String::Concat(
            textBox1->Text, myDataObject->GetData( "System.String", true )->ToString() );
   }

private void GetMyData3() {
    // Creates a new data object using a string and the text format.
    string myString = "My new text string";
    DataObject myDataObject = new DataObject(DataFormats.Text, myString);
 
    // Prints the string in a text box with autoconvert = false.
    if(myDataObject.GetData("System.String", false) != null) {
       // Prints the string in a text box.
       textBox1.Text = myDataObject.GetData("System.String", false).ToString() + '\n';
    } else
        {
            textBox1.Text = "Could not find data of the specified format" + '\n';
        }

        // Prints the string in a text box with autoconvert = true.
        textBox1.Text += myDataObject.GetData("System.String", true).ToString();
 }

Private Sub GetMyData3()
    ' Creates a new data object using a string and the text format.
    Dim myString As String = "My new text string"
    Dim myDataObject As New DataObject(DataFormats.Text, myString)
    
    ' Prints the string in a text box with autoconvert = false.
    If (myDataObject.GetData("System.String", False) IsNot Nothing) Then
        ' Prints the string in a text box.
        textBox1.Text = myDataObject.GetData("System.String", False).ToString() & ControlChars.Cr
    Else
        textBox1.Text = "Could not find data of the specified format" & ControlChars.Cr
    End If 
    ' Prints the string in a text box with autoconvert = true.
    textBox1.Text += myDataObject.GetData("System.String", True).ToString()
End Sub

注解

autoConvert如果 参数为 true ，并且此方法找不到指定格式的数据，则会尝试将数据转换为格式。 如果无法将数据转换为指定的格式，或者如果数据存储时自动转换设置为 false，则此方法返回 null。

autoConvert如果 参数为 false，则此方法返回指定格式的数据，或者null找不到此格式的数据。

若要确定数据是否与 数据关联或可转换为 格式，请在调用 之前调用 GetDataPresentGetData。 调用 GetFormats 此 DataObject中存储的数据的有效格式列表。

另请参阅

• SetData(String, Boolean, Object)
• GetDataPresent(Type)
• DataFormats
• GetFormats(Boolean)

public:
 virtual System::Object ^ GetData(System::String ^ format);

public virtual object GetData (string format);

public virtual object? GetData (string format);

abstract member GetData : string -> obj
override this.GetData : string -> obj

Public Overridable Function GetData (format As String) As Object

参数

返回

与指定格式关联的数据，或为 null。

实现

示例

下面的代码示例检索存储在 中的数据 DataObject。 首先，使用文本数据创建新的 DataObject 。 然后，检索数据，将其格式指定为字符串，并显示在文本框中。

此代码要求 textBox1 已创建 。

private:
   void AddMyData3()
   {
      // Creates a component to store in the data object.
      Component^ myComponent = gcnew Component;
      
      // Creates a new data object.
      DataObject^ myDataObject = gcnew DataObject;
      
      // Adds the component to the DataObject.
      myDataObject->SetData( myComponent );
      
      // Prints whether data of the specified type is in the DataObject.
      Type^ myType = myComponent->GetType();
      if ( myDataObject->GetDataPresent( myType ) )
      {
         textBox1->Text = String::Concat( "Data of type ", myType,
            " is present in the DataObject" );
      }
      else
      {
         textBox1->Text = String::Concat( "Data of type ", myType,
            " is not present in the DataObject" );
      }
   }

private void AddMyData3() {
    // Creates a component to store in the data object.
    Component myComponent = new Component();
 
    // Creates a new data object.
    DataObject myDataObject = new DataObject();
 
    // Adds the component to the DataObject.
    myDataObject.SetData(myComponent);
 
    // Prints whether data of the specified type is in the DataObject.
    Type myType = myComponent.GetType();
    if(myDataObject.GetDataPresent(myType))
       textBox1.Text = "Data of type " + myType.ToString() + 
       " is present in the DataObject";
    else
       textBox1.Text = "Data of type " + myType.ToString() +
       " is not present in the DataObject";
 }

Private Sub AddMyData3()
    ' Creates a component to store in the data object.
    Dim myComponent As New Component()
    
    ' Creates a new data object.
    Dim myDataObject As New DataObject()
    
    ' Adds the component to the DataObject.
    myDataObject.SetData(myComponent)
    
    ' Prints whether data of the specified type is in the DataObject.
    Dim myType As Type = myComponent.GetType()
    If myDataObject.GetDataPresent(myType) Then
        textBox1.Text = "Data of type " & myType.ToString() & _
            " is present in the DataObject"
    Else
        textBox1.Text = "Data of type " & myType.ToString() & _
            " is not present in the DataObject"
    End If
End Sub

注解

如果此方法找不到指定格式的数据，它会尝试将数据转换为格式。 如果无法将数据转换为指定格式，或者如果数据存储时自动转换设置为 false，则此方法返回 null。

若要确定数据是否与 数据关联或可转换为 格式，请在调用 之前调用 GetDataPresentGetData。 调用 GetFormats 此 DataObject中存储的数据的有效格式列表。

另请参阅

• SetData(String, Boolean, Object)
• GetDataPresent(Type)
• DataFormats
• GetFormats(Boolean)

public:
 virtual System::Object ^ GetData(Type ^ format);

public virtual object GetData (Type format);

public virtual object? GetData (Type format);

abstract member GetData : Type -> obj
override this.GetData : Type -> obj

Public Overridable Function GetData (format As Type) As Object

参数

返回

与指定格式关联的数据，或为 null。

实现

示例

下面的代码示例检索存储在 中的数据 DataObject。 首先， DataObject 使用组件创建新的 。 然后，检索数据并指定其类型。 检索到的数据类型显示在文本框中。

此代码要求 textBox1 已创建 。

private:
   void GetMyData()
   {
      // Creates a component to store in the data object.
      Component^ myComponent = gcnew Component;
      
      // Creates a new data object and assigns it the component.
      DataObject^ myDataObject = gcnew DataObject( myComponent );
      
      // Creates a type to store the type of data.
      Type^ myType = myComponent->GetType();
      
      // Retrieves the data using myType to represent its type.
      Object^ myObject = myDataObject->GetData( myType );
      if ( myObject != nullptr )
      {
         textBox1->Text = String::Format( "The data type stored in the DataObject is: {0}",
            myObject->GetType()->Name );
      }
      else
      {
         textBox1->Text = "Data of the specified type was not stored in the DataObject.";
      }
   }

private void GetMyData() {
    // Creates a component to store in the data object.
    Component myComponent = new Component();
 
    // Creates a new data object and assigns it the component.
    DataObject myDataObject = new DataObject(myComponent);
 
    // Creates a type to store the type of data.
    Type myType = myComponent.GetType();
 
    // Retrieves the data using myType to represent its type.
    Object myObject = myDataObject.GetData(myType);
    if(myObject != null)
       textBox1.Text = "The data type stored in the DataObject is: " +
       myObject.GetType().Name;
    else
       textBox1.Text = "Data of the specified type was not stored " +
       "in the DataObject.";
 }

Private Sub GetMyData()
    ' Creates a component to store in the data object.
    Dim myComponent As New Component()
    
    ' Creates a new data object and assigns it the component.
    Dim myDataObject As New DataObject(myComponent)
    
    ' Creates a type to store the type of data.
    Dim myType As Type = myComponent.GetType()
    
    ' Retrieves the data using myType to represent its type.
    Dim myObject As Object = myDataObject.GetData(myType)
    If (myObject IsNot Nothing) Then
        textBox1.Text = "The data type stored in the DataObject is: " & myObject.GetType().Name
    Else
        textBox1.Text = "Data of the specified type was not stored " & "in the DataObject."
    End If
End Sub

注解

如果此方法找不到指定格式的数据，它会尝试将数据转换为格式。 如果无法将数据转换为指定格式，或者如果数据存储时自动转换设置为 false，则此方法返回 null。

若要确定数据是否与 数据关联或可转换为 格式，请在调用 之前调用 GetDataPresentGetData。 调用 GetFormats 此 DataObject中存储的数据的有效格式列表。

另请参阅

• SetData(String, Boolean, Object)
• Type
• GetDataPresent(Type)
• DataFormats
• GetFormats(Boolean)