Accessing the items in a DataWindow
You can access data values in a DataWindow by using methods
or DataWindow data expressions. Both methods allow you to access
data in any buffer and to get original or current values.
The method you use depends on how much data you are accessing
and whether you know the names of the DataWindow columns when the
script is compiled.
For guidelines on deciding which method to
use, see the DataWindow Reference.
Using methods
There are several methods for manipulating data in a DataWindow
control.
These methods obtain the data in a specified row and column
in a specified buffer (Web DataWindow methods have separate methods
for overloaded versions):
-
PowerBuilder
GetItemDate, GetItemDateTime, GetItemDecimal, GetItemNumber,
GetItemString, GetItemTime -
Web ActiveX
GetItemDate, GetItemNumber, GetItemString
-
Web DataWindow server component
GetItemDate, GetItemDateByColNum, GetItemDateByColNumEx, GetItemDateEx, GetItemDateTime,
GetItemDateTimeByColNum, GetItemDateTimeByColNumEx, GetItemDateTimeEx,
GetItemNumber, GetItemNumberByColNum, GetItemNumberByColNumEx, GetItemNumberEx,
GetItemStatus, GetItemStatusByColNum, GetItemString, GetItemStringByColNum,
GetItemStringByColNumEx, GetItemStringEx, GetItemTime, GetItemTimeByColNum, GetItemTimeByColNumEx,
GetItemTimeEx
This method sets the value of a specified row and column:
-
PowerBuilder
and Web ActiveXSetItem
-
Web DataWindow server component
SetItemDate, SetItemDateByColNum, SetItemDateTime, SetItemDateTimeByColNum,
SetItemNumber, SetItemNumberByColNum, SetItemStatus, SetItemStatusByColNum, SetItemString,
SetItemStringByColNum, SetItemTime, SetItemTimeByColNum
For example, the following statement, using PowerBuilder syntax,
assigns the value from the empname column of the first row to the
variable ls_Name in the Primary buffer:
|
1 |
ls_Name = dw_1.<span>GetItemString</span> (1, "empname") |
This PowerBuilder statement sets the value of the empname
column in the first row to the string Waters:
|
1 |
dw_1.<span>SetItem</span>(1, "empname", "Waters") |
Uses
You call the GetItem methods to obtain the data that has been
accepted into a specific row and column. You can also use them to
check the data in a specific buffer before you update the database.
You must use the method appropriate for the column’s datatype.
For more information about the methods listed
above, see the DataWindow Reference.
Using expressions
DataWindow data expressions refer to single items, columns,
blocks of data, selected data, or the whole DataWindow.
The way you construct data expressions depends on the environment:
-
PowerBuilder
Use dot notation
-
Web ActiveX
Data expressions are not supported
Expressions in PowerBuilder
The Object property of the DataWindow control lets you specify
expressions that refer directly to the data of the DataWindow object
in the control. This direct data manipulation allows you to access
small and large amounts of data in a single statement, without calling methods:
|
1 |
dw_1.Object.jobtitle[3] = "Programmer" |
The next statement sets the value of the first column in the
first row in the DataWindow to Smith:
|
1 |
dw_1.Object.Data[1,1] = "Smith" |
For complete instructions on how to construct
DataWindow data expressions, see the DataWindow Reference.