问题
On the JSON website here, it explains the different possibilities of JSON 'objects'. However, in the numbers section, these appear:
e | e+ | e- | E | E+ | E-
1 - What do these represent?
In searching for an answer, <E> appears alot.
2 - Is <E> related to the above e|Es?
回答1:
It's the notation JSON (and most programming languages) use for scientific notation. Scientific notation is used to denote very large or small floating-point numbers. The e (or equivalently E) is equivalent to "×10^". For example,
3.7e-5 = 3.7E-5 = 3.7×10-5 = 0.000037
Positive or negative exponents may be used, and in the case of positive exponents, the + symbol may be omitted:
6.02e+23 = 6.02e23 = 6.02×1023 = 602 sextillion
More details are available at the Wikipedia article on scientific notation.
回答2:
The letter e looks a lot like the mathematical constant e (the 2.71828 thing) so languages usually let you use E instead. As shown by nandhp, it does the same thing as e.
来源：https://stackoverflow.com/questions/13617818/json-e-and-json-e