Tips on improving the readability of JS code

Logical flattening of

We work, may encounter some more complex logic, such as: Meet the condition 1, or XX, meet the conditions 2, or XX ... This is all satisfying Oo, written out about it:

The code is as follows	Copy Code
if (condition1) { if (condition2) { if (Condition3) { Todo A Lot } else { Do ZZ } } else { Do Oo } } else { Do xx }

The result is that logical nesting is complicated and difficult to read. It's even worse if you catch the indentation and don't do well or change lines. At this time, it is usually possible to interrupt code execution early to make the logic flat. Methods for early interruption include return, throw, and die () and exit () in PHP. The following is the rearrangement code:

The code is as follows	Copy Code
if (!condition1) { Do xx Return } if (!condition2) { Do Oo Return } if (!condition3) { Do ZZ Return } Todo A Lot

Of course, this approach is also applicable where exceptions are excluded. There are even radical statements that should not use else, but should be interrupted so early. I think that's a bit too much, if ... else ... The meaning is very clear.

Shortening the long-length logic judgment

There is an unwritten rule from the ancient times, a line of code 80 characters. As the display becomes larger, the old rules should be broken. But a single line of code too long will look very tired, so we still need to control. Very long code often appears in the logical judgment, such as the game's common test bullets have not hit the player's code, written in a better format is probably the case:

The code is as follows	Copy Code
if (Bullet.x > enemy.x + enemy.width | | bullet.y > enemy.y + enemy.height | | bullet.x + bullet.width < enemy.x | | Bullet.y + Bullet.width < enemy.y) { Console.log (' missed '); }

It's not too short. Sometimes we have to add enemy.damagable,!enemy.immunephysical and other conditions to judge, this line is very long written. This time we need to use a little skill to shorten it. There may be many ways of thinking, which is to refine the "purpose"--to refine the purpose of a set of judgments into a variable that is both readable and shortens the code. Now let's use a piece of code to illustrate this:

The code is as follows	Copy Code
var isgod =!enemy.damagable | | Eneymy.immunephysical,//judge whether the enemy can not attack/God mode Ishit = Bullet.hittest (eneymy); "Collision detection" with that large string of extraction methods just now. if (!isgod && ishit) { Enemy.die (); }

Summary

Both of these tips are simple, but the readability of the code is significant. The combination of various kinds of tricks will make the code more readable and easier to maintain.