Upgrading a control has three types of work:

1) upgrading the object model and members in logic

Good news is that this is the same as upgrading a standard (i.e. non-control) API

You will typically name the replacement control in the coClass a the bottom of the IDF. For example:

... 
   <coclass id="fpText" migName="System.Windows.Forms.RichTextBox" migStatus="External" role="control">
      <subclass id="IfpText"/>
      <subclass id="_DfpText"/>
   </coclass>
   <coclass id="fpMask" migName="System.Windows.Forms.MaskedTextBox" migStatus="External" role="control">
      <subclass id="IfpMask"/>
      <subclass id="_DfpMask"/>
   </coclass>
   <coclass id="fpDateTime" migName="RadDateTimePicker" role="control">
      <subclass id="IfpDateTime"/>
      <subclass id="_DfpDateTime"/>
   </coclass>
   <coclass id="fpDoubleSingle" migName="System.Windows.Forms.NumericUpDown" migStatus="External" role="control">
      <subclass id="IfpDoubleSingle"/>
      <subclass id="_DfpDoubleSingle"/>
   </coclass>
   <coclass id="fpLongInteger" migName="System.Windows.Forms.NumericUpDown" migStatus="External" role="control">
      <subclass id="IfpLongInteger"/>
      <subclass id="_DfpLongInteger"/>
   </coclass>

Notice that adding role=control is needed to make sure the objects are added to their parent containers

If a control is being migrated to a component, do not use role=control

2) upgrading event handlers

event arg types
event name changes
event handler arguiments -- these are statements added to the event handler to setup the old style event args as local variables in the handler.

 <event id="ItemClick" netName="ItemClick" migStatus="mscomctl" role="event" 
             netHandler="System.Windows.Forms.ListViewItemSelectionChangedEventHandler" 
             netArgs="ListViewItemSelectionChangedEventArgs" migPattern="ItemSelectionChanged" >
         <argument id="item" type="ListItem" status="ByVal" migPattern="%1d = e.Item" />
</event>

3) Designer code -- property initialization

these are specifications for what properties to set in teh designer.cs code file adn how to set them

<!--
********************************************************** 
* Statusbar Designer Code 
********************************************************** 
-->
   <migClass id="NetControl.StatusBar" 
             migName="System.Windows.Forms.StatusStrip"
             parent="StatusBar"
   >
      <property id="Font" value="Font" type="FontInfo" 
                nPram="3"
                vbnPattern="New System.Drawing.Font(\s%1d\s, %2d!, %3d, System.Drawing.GraphicsUnit.Point, CType(0,Byte))"
                cshPattern="new System.Drawing.Font(\s%1d\s, %2dF, %3d, System.Drawing.GraphicsUnit.Point, (System.Byte)(0))"
      />
      <property id="Location"
                value="(Left,Top)"
                nPram="2"
                vbnPattern="New System.Drawing.Point(%1d, %2d)"
                cshPattern="new System.Drawing.Point(%1d, %2d)"
      />
      <property id="Name" type="string"
                value="SYM.name"
      />
      <property id="Size"
                value="(Width,Height)"
                nPram="2"
                vbnPattern="New System.Drawing.Size(%1d, %2d)"
                cshPattern="new System.Drawing.Size(%1d, %2d)"
      />
      <property id="TabIndex" type="Integer"
                value="TabIndex"
                default="0"
      />
   </migClass>

Setting a color property in the designer

The following example shows how to map a color in designer code.

<migClass id="NetControl.fpDoubleSingle" migName="NumericUpDown" parent="fpDoubleSingle">
    <property id="BackColor" type="OLE_COLOR"
              value="IfpDoubleSingle.BackColor"
                nPram="3"
                migPattern="System.Drawing.Color.FromArgb(%3d, %2d, %1d)"
                default="System.Drawing.SystemColors.WindowText"
    />

Browser not supported