ade_altpdefine

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ade_altpdefine

Property Alteration Functions

Creates a property alteration expression.

ade_id ade_altpdefine(

char* property,

struct resbuf* value);

Returns a property alteration expression ID or ADE_NULLID.

Note  If you use a range table expression instead of an explicit value argument, you must represent it in the resbuf as all one string.

You must release the resbuf.

Using a Range Table

The following code generates a property alteration expression that adds a yellow text object to each queried entity. The text object displays which layer the entity came from. Note how the value argument is prepared by using ads_buildlist to define and populate the required resbuf.

char* propName = "textobject";
struct resbuf* pPropValueRb = ads_buildlist
    (
        RTLB,
            RTLB,
            RTSTR, "color", RTSTR, "yellow",
            RTDOTE,
            RTLB,
            RTSTR, "textvalue", RTSTR, ".Layer",
            RTDOTE,
        RTLE, 0
    );
ade_id propAltID = ade_altpdefine(propName, pPropValueRb);
if (ADE_NULLID != propAltID) {
    acutPrintf(
        "\nThe property alteration expression ID is: %.0lf"
        , propAltID);
}
else {
    acutPrintf(
        "\nNo property alteration expression ID was set");
}
acutRelRb(pPropValueRb);

A list of one or more property alteration expressions constitutes a property alteration definition. If there is a current property alteration definition when you create a property alteration expression, the new expression is added to it. When you execute a Draw query, each queried entity is altered in accord with the current property alteration definition.

The following table lists the alterable properties:

To add a hatch pattern to each queried entity, as long as it is a closed polygon, specify "hatch" for the property argument. The value argument is then a list of dotted pairs. Each dotted pair is composed of a hatch property and a string value.

To create a text object for each queried entity, specify "textobject" for the property argument. The value argument is then a list of dotted pairs. Each dotted pair is composed of a text object property and a string value. The value element in the dotted pair can be an explicit value or a range table expression that determines a value.