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**DDEQUERY(** [ //application// ] [, //topic// ] **)**

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| **DDEQUERY** | Returns currently executing DDE servers. |
| //application// | A string constant or variable containing the name of the application to query. For most applications, this is the name of the application. If omitted, all registered //applications// registered with the specified //topic// are returned. |
| //topic// | A string constant or variable containing the name of the application-specific topic to query. If omitted, all //topics// for the //application// are returned. |

The **DDEQUERY** procedure returns a string containing the names of the currently available DDE server //applications// and their //topics//.

If the //topic// parameter is omitted, all //topics// for the specified //application// are returned. If the //application// parameter is omitted, all registered //applications// registered with the specified //topic// are returned. If both parameters are omitted, DDEQUERY returns all currently available DDE servers.

The format of the data in the return string is //application:topic// and it can contain multiple //application// and //topic// pairs delimited by commas (for example, 'Excel:MySheet.XLS,ClarionApp:DataFile.DAT').

**Return Data Type:     **STRING

**Example:**

** !This example code does not handle DDEADVISE**

**WinOne WINDOW,AT(0,0,160,400)**

**       END**

**SomeServer   LONG**

**ServerString STRING(200)**

** CODE**

** OPEN(WinOne)**

** LOOP**

**  ServerString = ****DDEQUERY****()                     !Return all registered servers**

**  IF NOT INSTRING('SomeApp:MyTopic',ServerString,1,1)**

**   MESSAGE('Open SomeApp, Please')**

**  ELSE**

**   BREAK**

**  END**

** END**

** SomeServer = DDECLIENT('SomeApp','MyTopic')    !Open as client**

** ACCEPT**

** END**

** DDECLOSE(SomeServer)**