Tree Model

Applies to TestComplete 15.64, last modified on June 12, 2024

This topic explains the concept and specifics of the Tree model of web test objects. For the general principles of web object identification, see Understanding Web Object Identification and Object Models.

About the Tree Model

The Tree model represents web page objects in a tree-like structure that reflects the nesting of HTML elements in the page markup. For example, suppose a web page contains a table with an input field. In the Tree model, it is represented as a Table object that has a child Cell object with a child TextBox object.

Tree model

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The Tree model is recommended for web testing and is used by default in all new TestComplete projects. Other models are obsolete and are supported for backward compatibility only. We do not recommend that you use them.

How Object Names Are Formed

In the object hierarchy that TestComplete generates for your tested web page or web application — you can view it in the tree section of the Object Browser — each web element has a name that is formed according to the following rules:

Object names in the Object Browser

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  • Most object names have the following format: ObjectType(ObjectIdentifier). They are formed by using the corresponding object properties - ObjectType and ObjectIdentifier.

    Names of objects that correspond to custom elements have the following format: CustomObjectType(ObjectIdentifier). They are formed by the CustomObjectType and ObjectIdentifier properties.

    ObjectType takes one of the values listed in the Object Types Used in the Tree Model topic. They are not the same as the tag names. For example, the A elements (links) have ObjectType of Link.

    The CustomObjectType value is based on the name under which the custom element is registered in the web application. To learn more, see About Support for Web Components.

    ObjectIdentifier has of the following values (in the order of precedence):

    • For Image objects (<img> elements) - the object’s namePropStr property value which holds the last component of the src URL (typically the file name).

    • For Button (<button> and <input type="button">), ResetButton (<input type="reset">) and SubmitButton (<input type="submit">) - the value attribute.

    • For Area objects (<area> elements) - the area’s title attribute value.

    • For other objects - the object’s id or name in the HTML code, changed as follows:

      • processed according to the dynamic identifier patterns specified in the project’s Object Identification properties,
      • all characters other than Latin letters (A..Z a..z) and digits replaced with underscores ( _ ),
      • subsequent underscores replaced with a single underscore,
      • leading underscores stripped.

      The project’s Identification attribute setting specifies which attribute - id or name - is used first.

    • The object’s zero-based index among the sibling objects of the same type.



  • The names of table cells have the following format: Cell(RowIndex, ColumnIndex), where RowIndex and ColumnIndex are the cell’s row and column numbers (zero-based) in the table.

  • The Alert, Confirm, Prompt and Login test objects are named by their name without any parameters. For example, Alert.

  • Some elements (for example hidden INPUT fields) are not displayed. See Web Elements Included in and Excluded From the Object Hierarchy for a full list.

There are other ways of addressing web elements in tests. If you use Name Mapping, you address the web elements by using custom names (aliases) you assign to them in the Name Mapping repository. You can also address web elements by using XPath expressions or CSS selectors. To learn more, see Understanding Web Object Identification and Object Models.

Dealing With Long Object Names

Since the Tree model reflects logical nesting of web page elements, the fully-qualified names of objects on web pages with complex markup can be quite long. For example:

// Using Name Mapping

// Not using Name Mapping

Such long object names can make your tests difficult to read.

There are several ways to avoid long object names in tests:

See Also

Classic Web Testing
Understanding Web Object Identification and Object Models
Web Object Types Used by Web and Hybrid Mobile Applications
Accessing DOM document Object

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