We’ll talk about that a lot in the text that follows. Sometimes they choose in ways that help them accurately represent their data.Worse yet is that people don’t always choose between the two approaches for consistent reasons. That can give XML flexibility and also make it confusing. The fact that elements each have a name also enables XML to have two approaches to indicating an element’s “keys+values,” whereas JSON only has one approach. Note the forward-slash before its greater-than sign:Įlements having names is a key aspect of XML. This single tag is equivalent to a tagset with nothing in the middle like the one above. In fact, there’s even a fancy shortcut for typing “empty” tagsets. If it doesn’t have anything between the tags, you can think of it a little like a row full of nothing but commas in a CSV file. The “element” is still a conceptual item that “exists” in your data, simply because you bothered to create a “tagset” to represent it. It doesn’t matter whether or not there’s anything typed between the tags (after the first greater-than, before the last less-than). The fact that the tagset exists in your text file means that it exists as a conceptual “ item” in your data. The second “tag” is meant to indicate the end of the element.The first “tag” is meant to indicate the beginning of the element.The second “tag” is distinguished from the first by having a forward-slash (“ /“) immediately after its less-than sign.Hence, together, they are called a “tagset.”.Each occurrence of the word is surrounded by less-than and greater-than signs, forming a “tag.”.( Click here if you need a refresher on what I mean by items, keys, and values.) The 2 punctuation options XML gives you to add “key-value pairs” to an item.The punctuation you use to “nest” items inside each other.The punctuation you use to indicate an “item”.In this first of three posts on XML, we’ll cover three topics: This gets a little detailed, so I’m breaking it into 3 posts published on the same day to give you a coffee break. We understand what kind of data XML can help us with. We’ve seen XML from a “ 30,000-foot view.” Beware “true emptiness” versus “text with 0 characters”.“Attributes”: no duplicate keys allowed.“Attributes”: no further nesting allowed.“Keys” & their “Values” - Approach 2 (“attributes”).“Keys” & their “Values” - Approach 1 (“more tagsets”).
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