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

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| **DDECLIENT** | Returns a new DDE client channel number. |
| //application// | A string constant or variable containing the name of the server application to link to. Usually, this is the name of the application. If omitted, the first DDE server application available is used. |
| //topic// | A string constant or variable containing the name of the application-specific topic. If omitted, the first topic available in the //application// is used. |

The **DDECLIENT** procedure returns a new DDE client channel number for the //application// and //topic//. If the //application// is not currently executing, DDECLIENT returns zero (0).

Typically, when opening a DDE channel as the client, the //application// is the name of the server application. The //topic// is a string that the //application// has either registered with Windows as a valid //topic// for the //application//, or represents some value that tells the //application// what data to provide. You can use the DDEQUERY procedure to determine the //applications// and //topics// currently registered with Windows.

**Return Data Type:     **LONG

**Example:**

**DDEReadVal  REAL**

**WinOne  WINDOW,AT(0,0,160,400)**

**         ENTRY(@s20),USE(DDEReadVal)**

**        END**

**ExcelServer LONG**

** CODE**

** OPEN(WinOne)**

**!Open as client to Excel spreadsheet:**

** ExcelServer = ****DDECLIENT****('Excel','MySheet.XLS')**

** IF NOT ExcelServer                    !If the server is not running**

**  MESSAGE('Please start Excel')        !alert the user to start it**

**  RETURN                               !and try again**

** END**

** DDEREAD(ExcelServer,DDE:auto,'R5C5',DDEReadVal)**

** ACCEPT**

**  CASE EVENT()**

**  OF EVENT:DDEdata                     !As changed data comes from Excel**

**   PassedData(DDEReadVal)              !process the new data**

**  END**

** END**

**See Also:**

[[ddequery  return registered dde servers .htm|DDEQUERY]]

[[ddewrite  provide data to dde client .htm|DDEWRITE]]

[[ddeserver  return dde server channel .htm|DDESERVER]]