Is there a memset function in JavaScript?

There is no memset() function in JavaScript; the memset() function is a "C/C" language initialization function. Its function is to set all the contents in a certain memory to a specified value. This function is usually for new applications. The memory is initialized, and this function cannot be used in JavaScript.

The operating environment of this tutorial: Windows 10 system, JavaScript version 1.8.5, Dell G3 computer.

Is there a memset function in JavaScript?

There is no memset() function in JavaScript

memset is the C/C language initialization function in the computer. Its function is to set all the contents in a certain memory to a specified value. This function usually initializes the newly requested memory.

void *memset(void *s, int ch, size_t n);

Function explanation: Replace the n bytes (typedef unsigned int size_t) following the current position in s with ch and return s.

memset: The function is to fill a given value in a memory block. It is the fastest way to clear a larger structure or array [1].

memset() function prototype is extern void *memset(void *buffer, int c, int count) buffer: is a pointer or array, c: is the value assigned to the buffer, count: is the length of the buffer .

Write a program below:

# include <stdio.h>
# include <string.h>
int main(void)
{
    int i;  //循环变量
    char str[10];
    char *p = str;
    memset(str, 0, sizeof(str));  //只能写sizeof(str), 不能写sizeof(p)
    for (i=0; i<10; ++i)
    {
        printf("%d\x20", str[i]);
    }
    printf("\n");
    return 0;
}

According to the different memset functions, the output results are also different, which are divided into the following situations:

memset(p, 0, sizeof(p));  //地址的大小都是4字节
0 0 0 0 -52 -52 -52 -52 -52 -52
memset(p, 0, sizeof(*p));  //*p表示的是一个字符变量, 只有一字节
0 -52 -52 -52 -52 -52 -52 -52 -52 -52
memset(p, 0, sizeof(str));
0 0 0 0 0 0 0 0 0 0
memset(str, 0, sizeof(str));
0 0 0 0 0 0 0 0 0 0
memset(p, 0, 10);  //直接写10也行, 但不专业
0 0 0 0 0 0 0 0 0 0

Related recommendations: javascript learning tutorial

The above is the detailed content of Is there a memset function in JavaScript?. For more information, please follow other related articles on the PHP Chinese website!