Chapter 5: Accessing DataWindow Object Properties in Code

Accessing DataWindow object property values in code

Two techniques

There are two ways to access property values in a DataWindow object:

Methods The Describe and Modify methods use strings to specify the property names. For example:
```
dw_1.Describe("empname.Border")
```
```
dw_1.Modify("empname.Border=1")
```
Expressions DataWindow property expressions use the Object property and dot notation. For example:
```
dw_1.Object.empname.Border = 1
```
```
li_border = Integer(dw_1.Object.empname.Border)
```

Which technique to use

The technique you use depends on the type of error checking you want to provide and on whether you know the names of the controls and properties you want to access when the script is compiled.

**Table 5-2: Error handling in DataWindow property expressions**
If you want to	Use
Use column and property names that are known when the script is compiled	An expression
Avoid extra nested tildes (and you know the column and property names you want to access)	An expression
Build a string at runtime that names controls and properties	A method
Use the DWRuntimeError to handle problems with incorrect control or property names	An expression in a try-catch block
Use the Error event to handle problems with incorrect control or property names	An expression and a script for the Error event
Avoid using the Error event (or DWRuntimeError) for handling problems with incorrect control or property names	A method and code that evaluates its return value

Using DataWindow expressions as property values

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