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**DDEREAD(** //channel, mode, item //[, //variable// ] **)**

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| **DDEREAD** | Gets data from a previously opened DDE client channel. |
| //channel// | A LONG integer constant or variable containing the client channel--the value returned by the DDECLIENT procedure. |
| //mode// | An EQUATE defining the type of data link: DDE:auto, DDE:manual, or DDE:remove (defined in EQUATES.CLW). |
| //item// | A string constant or variable containing the application-specific name of the data item to retrieve. |
| //variable// | The name of the variable to receive the retrieved data. If omitted and //mode// is DDE:remove, all links to the //item// are canceled. |

The **DDEREAD** procedure allows a DDE client program to read data from the //channel// into the //variable//. The type of update is determined by the //mode// parameter. The //item// parameter supplies some string value to the server application that tells it what specific data item is being requested. The format and structure of the //item// string is dependent upon the server application.

If the //mode// is DDE:auto, the //variable// is continually updated by the server (a "hot" link). An EVENT:DDEdata is generated each time the //variable// is updated by the server.

If the //mode// is DDE:manual, the //variable// is updated once and no event is generated. Another DDEREAD request must be sent to the server to check for any changed value (a "cold" link).

If the //mode// is DDE:remove, a previous "hot" link to the //variable// is terminated. If the //mode// is DDE:remove and //variable// is omitted, all previous "hot" links to the //item// are terminated, no matter what //variables// were linked. This means the client must send another DDEREAD request to the server to check for any changed value.

**Errors Posted:**

| 601 | Invalid DDE Channel |
| 602 | DDE Channel Not Open |
| 605 | Time Out |

**Events Generated:**

These events are posted to the client application:

| EVENT:DDEdata | A server has supplied an updated data item for a hot link. |
| EVENT:DDEclosed | A server has terminated the DDE link. |

**Example:**

**WinOne  WINDOW,AT(0,0,160,400)**

**        END**

**ExcelServer LONG(0)**

**DDEReadVal  REAL**

** 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**

**  CLOSE(WinOne)**

**  RETURN**

** END**

**!Request continual update from server:**

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

**ACCEPT**

**  CASE EVENT()**

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

**   PassedData(DDEReadVal)     ! call proc to 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]]