内存值输出

[dxf5457]

如何将内存的值输出呢？如整形777输出的字符串为：09 03

[newtee]

%x 16进制输出

[hongwenjun]

#include <iostream>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>

void printBinStr(const void* buf , size_t size);
void printHexStr(const void* buf , size_t size);

void test();

int main(int argc, char* argv[])
{

//   test();


    int seven  = 777;
    printBinStr(&seven , sizeof(seven));
    printHexStr(&seven , sizeof(seven));

    return 0;
}

void test()
{
    char arr[100];
    for (int i = 0; i != 100  ; ++i) {
        arr[i] = i + '1';
    }
    printBinStr(arr , sizeof(arr));

    putchar('\n');
// 打印文件
    const char* filename =  "main.cpp";

    FILE* f = fopen(filename, "rb");
    if (!f) {
        std::cerr << "Error: Cannot open File " << std::endl;
        exit(-1) ;
    }
    // Get file size:
    fseek(f, 0, SEEK_END);
    const long N = ftell(f);
    fclose(f);

    f = fopen(filename, "rb");
    char* buf = new char[N + 1];
    fread(buf, 1, N, f);
    buf[N] = '\0';

    printHexStr(buf , N);
}

void printBinStr(const void* buf , size_t size)
{
    unsigned char* str = (unsigned char*)buf;
    char line[512] = {0};
    const size_t lineLength = 6; // 每行6个字符
    char text[24] = {0};
    char sbin[10] = {0};
    char* pc;
    int textLength = lineLength;


    for (size_t ix = 0 ; ix < size ; ix += lineLength) {
        sprintf(line, "%.8xh: ", ix);
// 打印二进制
        for (size_t jx = 0 ; jx != lineLength ; jx++) {

            itoa(* (str + ix + jx),   sbin,   2);       //转换成字符串，进制基数为2

            if (ix + jx >= size) {
                sprintf(line + (11 + jx * 9), "         "); // 处理最后一行空白
                if (ix + jx == size)
                    textLength = jx;  // 处理最后一行文本截断
            } else
                sprintf(line + (11 + jx * 9), "%08s ", sbin);
        }
// 打印字符串
        {
            memcpy(text, str + ix, lineLength);
            pc = text;
            while (pc != text + lineLength) {
                if ((unsigned char)*pc < 0x20) // 空格之前为控制码
                    *pc = '.';                 // 控制码转成'.'显示
                pc++;
            }
            text[textLength] = '\0';
            sprintf(line + (11 + lineLength * 9), "; %s", text);
        }

        printf("%s\n", line);
    }
}

void printHexStr(const void* buf , size_t size)
{
    unsigned char* str = (unsigned char*)buf;
    char line[512] = {0};
    const size_t lineLength = 16; // 8或者32
    char text[24] = {0};
    char* pc;
    int textLength = lineLength;

    for (size_t ix = 0 ; ix < size ; ix += lineLength) {
        sprintf(line, "%.8xh: ", ix);
// 打印16进制
        for (size_t jx = 0 ; jx != lineLength ; jx++) {
            if (ix + jx >= size) {
                sprintf(line + (11 + jx * 3), "   "); // 处理最后一行空白
                if (ix + jx == size)
                    textLength = jx;  // 处理最后一行文本截断
            } else
                sprintf(line + (11 + jx * 3), "%.2X ", * (str + ix + jx));
        }
// 打印字符串
        {
            memcpy(text, str + ix, lineLength);
            pc = text;
            while (pc != text + lineLength) {
                if ((unsigned char)*pc < 0x20) // 空格之前为控制码
                    *pc = '.';                 // 控制码转成'.'显示
                pc++;
            }
            text[textLength] = '\0';
            sprintf(line + (11 + lineLength * 3), "; %s", text);
        }

        printf("%s\n", line);
    }
}

[四流程序员的业余生活]

printf（“%p”，777）

[jiemo1123]

%p，输出指针(地址)

[赵4老师]

void HexDump(char *buf,int len) {
    int i,j,k;
    char binstr[80];

    for (i=0;i<len;i++) {
        if (0==(i%16)) {
            sprintf(binstr,"%04x -",i);
            sprintf(binstr,"%s %02x",binstr,(unsigned char)buf[i]);
        } else if (15==(i%16)) {
            sprintf(binstr,"%s %02x",binstr,(unsigned char)buf[i]);
            sprintf(binstr,"%s  ",binstr);
            for (j=i-15;j<=i;j++) {
                sprintf(binstr,"%s%c",binstr,('!'<buf[j]&&buf[j]<='~')?buf[j]:'.');
            }
            printf("%s\n",binstr);
        } else {
            sprintf(binstr,"%s %02x",binstr,(unsigned char)buf[i]);
        }
    }
    if (0!=(i%16)) {
        k=16-(i%16);
        for (j=0;j<k;j++) {
            sprintf(binstr,"%s   ",binstr);
        }
        sprintf(binstr,"%s  ",binstr);
        k=16-k;
        for (j=i-k;j<i;j++) {
            sprintf(binstr,"%s%c",binstr,('!'<buf[j]&&buf[j]<='~')?buf[j]:'.');
        }
        printf("%s\n",binstr);
    }
}

[清天灵月]

看到 2L 的回答，哥震惊了！！

[清天灵月]

内存中存储的都是 二进制数 ， 即使整形 777 输出09 03 也是十六进制数，这也仅是为了便于阅读！