Dynamic Data Exchange from the User's Point of View

Custom Search

The following example illustrates illustrates how two DDE applications can cooperate, as seen from the user's point of view.

A spreadsheet user wants to use Microsoft® Excel to track the price of a particular stock on the New York Stock Exchange. The user has a Win32-based application called Quote that in turn has access to NYSE data. The DDE conversation between Microsoft Excel and Quote takes place as follows:

The user initiates the conversation by supplying the name of the application (Quote) that will supply the data and the particular topic of interest (NYSE). The resulting DDE conversation is used to request quotes on specific stocks.
Microsoft Excel broadcasts the application and topic names to all DDE applications currently running in the system. Quote responds, establishing a conversation with Microsoft Excel about the NYSE topic.
The user can then create a spreadsheet formula in a cell that requests that the spreadsheet be automatically updated whenever a particular stock quotation changes. For example, the user could request an automatic update whenever a change occurs in the selling price of ZAXX stock by specifying the following Microsoft Excel formula:

='Quote'|'NYSE'!ZAXX

The user can terminate the automatic updating of the ZAXX stock quotation at any time. Other data links that were established separately (such as for quotations for other stocks) still will remain active under the same NYSE conversation.
The user can also terminate the entire conversation between Microsoft Excel and Quote on the NYSE topic, so that no specific data links on that topic can be established without initiating a new conversation.

Last news from Greatis Software

    Nostalgia .Net     .Net is powerful, but not all-powerful, so sometimes we need to use Win32 API for our .Net applications. It's simple enough with Platform Invoke if you have Win32 skill, but we do not always have time to dig the ancient documentation, declare the special types that are compatible with Win32, find the values of the Win32's constants and so on. Nostalgia .Net offers several simple-to-use classes, and components that will allow you to forget about the headache of Win32 and just use the power of Win32 in your application the same way as you use the native. Net classes. More »

Recommended software for developers

    Ultimate Pack     Component pack for Delphi and C++ Builder that contains runtime form designer, runtime object inspector, print suite and much more for the very special price. More »

    Form Designer .Net     Unique runtime form design solution that allows to edit any form in .Net WinForms application at runtime with full source codes for only 300 euro! More »

    Print Suite .Net     Print Suite .Net is a set of components for easy printing texts, images and grids from your WinForms applications. Full C# source codes are available More »

    Gradient Controls .Net     Gradient Controls .Net offers controls with gradient background feature. Labels, panels and so on... Full C# source codes are available More »

    Greatis iGrid     iGrid plots drawing grid right over your desktop, so you can use it everywhere, with any drawing application without any special plugins for different graphic editors. More »

All the contacts and projects

Dmitry Vasiliev (just.dmitry)

More Online Helps

Win32 Programmer's Reference
Win32 Multimedia Programmer's Reference
OLE Programmer's Reference
Microsoft Windows Pen API Programmer's Reference
Microsoft Windows Sockets 2 Reference
Microsoft Windows Telephony API (TAPI) Programmer's Reference
Unix Manual Pages

greatis just4fun network