什么方括号意味着数组初始化用C？ [英] What do square brackets mean in array initialization in C?

问题描述

static uint8_t togglecode[256] = {
    [0x3A] CAPSLOCK,
    [0x45] NUMLOCK,
    [0x46] SCROLLLOCK
};

什么是的意义[0x3A] 在这里？我只学会了像 INT语句[2] = {1，2};

What's the meaning of [0x3A] here? I have only learned statements like int a[2] = {1, 2};

推荐答案

这意味着初始化的 N 的-th数组的元素。你给出的例子将意味着：

It means initialise the n-th element of the array. The example you've given will mean that:

togglecode[0x3A] == CAPSLOCK
togglecode[0x45] == NUMLOCK
togglecode[0x46] == SCROLLLOCK

这些被称为指定初始化，并且实际C99标准的一部分。然而，如果没有语法 = 不是。从该页面：

These are called "designated initializers", and are actually part of the C99 standard. However, the syntax without the = is not. From that page:

这一个可选的语法，因为GCC 2.5这已经过时了，但GCC仍然接受是写 [指数] 元素值，没有 = 。

An alternative syntax for this which has been obsolete since GCC 2.5 but GCC still accepts is to write [index] before the element value, with no =.

这篇关于什么方括号意味着数组初始化用C？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！