One of the major improvements in WebForms Core 2.1 is the expansion of WebForms Place Criteria (WPC).
WPC is a DSL built into WebForms Core for selecting, filtering, and manipulating HTML elements and groups of DOM elements. At its basic level, WPC provides selectors for finding elements by ID, Name, Tag, Class, and Attribute, as well as navigating through children, parents, the current element, the target element, Document, Window, HTML, Head, Root, and other locations within the DOM. Elements can also be selected by index, all matching elements can be retrieved, and selection paths can be combined using methods such as Child() and Parent().
WPC selectors are used to find (or select) HTML elements (and beyond) that you want to apply changes to. WPC is a competitor to CSS Selectors, yet it also covers the syntax of CSS Selectors. WPC is only available in WebForms Core and is not available outside of this technology.
However, the main focus of this article is WebForms Place Criteria, or Criteria. Criteria extends the basic WPC selection mechanism by allowing developers to filter and evaluate already-selected elements based on their text content, attributes, tag names, visibility, enabled or disabled state, checked state, DOM relationships, position, ranges, and element sets. Criteria supports different operators and allows multiple conditions to be chained together, making it possible to create complex selections that cannot be expressed using only an ID, Class, Tag, or other basic selector.
