Microsoft KB Archive/171438: Difference between revisions
From BetaArchive Wiki
(importing KB archive) |
m (Text replacement - """ to """) |
||
Line 67: | Line 67: | ||
<li><p>Place the following code in a program file and add the program file to a project named OLETest. Compile the project into an OLE DLL or EXE named OLETest.</p> | <li><p>Place the following code in a program file and add the program file to a project named OLETest. Compile the project into an OLE DLL or EXE named OLETest.</p> | ||
<pre class="codesample"> DEFINE CLASS ARRAYTEST AS CUSTOM OLEPUBLIC | <pre class="codesample"> DEFINE CLASS ARRAYTEST AS CUSTOM OLEPUBLIC | ||
NAME = | NAME = "arraytest" | ||
PROCEDURE DOIT | PROCEDURE DOIT | ||
Line 74: | Line 74: | ||
INSERT INTO foot (ONE,TWO,THREE,FOUR) VALUES ; | INSERT INTO foot (ONE,TWO,THREE,FOUR) VALUES ; | ||
(MYARRAY[1],MYARRAY[2],MYARRAY[3],MYARRAY[4]) | (MYARRAY[1],MYARRAY[2],MYARRAY[3],MYARRAY[4]) | ||
MYARRAY [1] = | MYARRAY [1] = "100" | ||
MYARRAY [2] = | MYARRAY [2] = "200" | ||
MYARRAY [3] = | MYARRAY [3] = "300" | ||
MYARRAY [4] = | MYARRAY [4] = "400" | ||
USE CURDIR() + | USE CURDIR() + "foot.dbf" | ||
INSERT INTO foot (ONE,TWO,THREE,FOUR) VALUES ; | INSERT INTO foot (ONE,TWO,THREE,FOUR) VALUES ; | ||
(MYARRAY[1],MYARRAY[2],MYARRAY[3],MYARRAY[4]) | (MYARRAY[1],MYARRAY[2],MYARRAY[3],MYARRAY[4]) | ||
Line 96: | Line 96: | ||
CLEAR ALL | CLEAR ALL | ||
DIMENSION MYARRAY[4] | DIMENSION MYARRAY[4] | ||
MYARRAY(1) = | MYARRAY(1) = "1" | ||
MYARRAY(2) = | MYARRAY(2) = "2" | ||
MYARRAY(3) = | MYARRAY(3) = "3" | ||
MYARRAY(4) = | MYARRAY(4) = "4" | ||
OX = CREATEOBJECT( | OX = CREATEOBJECT("OLEtest.arraytest") | ||
OX.DOIT(@MYARRAY) | OX.DOIT(@MYARRAY) | ||
?OX.Name | ?OX.Name | ||
? | ?"MyArray from Calling Program" | ||
DISPLAY MEMORY LIKE MYARRAY | DISPLAY MEMORY LIKE MYARRAY | ||
RELEASE OX | RELEASE OX | ||
Line 110: | Line 110: | ||
BROWSE NOWAIT | BROWSE NOWAIT | ||
</pre></li> | </pre></li> | ||
<li>Notice the first record of table | <li>Notice the first record of table "foot" contains the values placed in the array by the calling program. The second record contains the values PROCEDURE DOIT placed in the array. The DISPLAY MEMORY LIKE MYARRAY command, however, contains the original values of the array. Even though it appears that we are passing the array by reference to the OLE object, Microsoft Visual FoxPro is passing it by value.</li></ol> | ||
Latest revision as of 11:05, 21 July 2020
Article ID: 171438
Article Last Modified on 5/12/2003
APPLIES TO
- Microsoft Visual FoxPro 3.0 Standard Edition
- Microsoft Visual FoxPro 3.0b Standard Edition
- Microsoft Visual FoxPro 5.0 Standard Edition
- Microsoft Visual FoxPro 5.0a
- Microsoft Visual FoxPro 3.0b for Macintosh
This article was previously published under Q171438
SYMPTOMS
Microsoft Visual FoxPro does not support passing arrays by reference to OLE objects.
STATUS
This behavior is by design.
MORE INFORMATION
Steps to Reproduce Behavior
Place the following code in a program file and add the program file to a project named OLETest. Compile the project into an OLE DLL or EXE named OLETest.
DEFINE CLASS ARRAYTEST AS CUSTOM OLEPUBLIC NAME = "arraytest" PROCEDURE DOIT PARAMETER MYARRAY EXTERNAL ARRAY MYARRAY INSERT INTO foot (ONE,TWO,THREE,FOUR) VALUES ; (MYARRAY[1],MYARRAY[2],MYARRAY[3],MYARRAY[4]) MYARRAY [1] = "100" MYARRAY [2] = "200" MYARRAY [3] = "300" MYARRAY [4] = "400" USE CURDIR() + "foot.dbf" INSERT INTO foot (ONE,TWO,THREE,FOUR) VALUES ; (MYARRAY[1],MYARRAY[2],MYARRAY[3],MYARRAY[4]) ENDPROC PROCEDURE INIT SET UDFPARMS TO REFERENCE CREATE TABLE foot ; (ONE C(10),TWO C(10), THREE C(10), FOUR C(10)) ENDPROC ENDDEFINE
After the OLE file is compiled, run the following code:
CLEAR CLEAR ALL DIMENSION MYARRAY[4] MYARRAY(1) = "1" MYARRAY(2) = "2" MYARRAY(3) = "3" MYARRAY(4) = "4" OX = CREATEOBJECT("OLEtest.arraytest") OX.DOIT(@MYARRAY) ?OX.Name ?"MyArray from Calling Program" DISPLAY MEMORY LIKE MYARRAY RELEASE OX RELEASE MYARRAY USE foot BROWSE NOWAIT
- Notice the first record of table "foot" contains the values placed in the array by the calling program. The second record contains the values PROCEDURE DOIT placed in the array. The DISPLAY MEMORY LIKE MYARRAY command, however, contains the original values of the array. Even though it appears that we are passing the array by reference to the OLE object, Microsoft Visual FoxPro is passing it by value.
Keywords: kbprb kbcode KB171438