我就废话不多说了,大家还是直接看代码吧~
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#include <time.h>
#include <sys/timeb.h>
void MainWindow::slot_clicked()
{
QString strRand;
int length = 32;
QString strTmp = "1234567890QWERTYUIOPASDFGHJKLZXCVBNM" ;
struct timeb timer;
ftime(&timer);
srand (timer. time * 1000 + timer.millitm); //毫秒种子
for ( int i = 0; i < length; i++ )
{
int j = rand ()%35;
strRand += strTmp.at(j);
}
qDebug() << strRand;
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补充知识:C/C++生成随机数字符串(错误方法和正确方法)
先说错误的方法。生成的10个随机数是一样的。
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#include <stdio.h>
#include <time.h>
#include <stdlib.h>
#include <string.h>
void make_rand_str( char *pchStr, int iLen)
{
time_t tCurTime = 0;
int iRandValue = 0;
int i = 0;
unsigned int state = 0;
if (NULL == pchStr || iLen <= 0)
{
return ;
}
tCurTime = time (NULL);
printf ( "\n***%ld***%u**\n" ,tCurTime ,(unsigned int )tCurTime);
srand ((unsigned int )tCurTime);
iRandValue = rand ();
snprintf(pchStr,iLen, "%d" ,iRandValue);
printf ( "\n====%s====\n" ,pchStr);
return ;
}
int main()
{
char str[20];
int i = 0;
for (i = 0; i < 10; i++)
{
memset (str,0, sizeof (str));
make_rand_str(str, sizeof (str));
// printf("\n====%s====\n",str);
}
return 0;
}
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正确的方法,生成了10个不一样的随机数
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#include <stdio.h>
#include <time.h>
#include <stdlib.h>
#include <string.h>
void make_rand_str( char *pchStr, int iLen, int num)
{
time_t tCurTime = 0;
int iRandValue = 0;
int i = 0;
unsigned int state = 0;
if (NULL == pchStr || iLen <= 0)
{
return ;
}
tCurTime = time (NULL);
printf ( "\n***%ld***%u**\n" ,tCurTime ,(unsigned int )tCurTime);
srand ((unsigned int )tCurTime);
for (i = 0;i < num; i++)
{
iRandValue = rand ();
snprintf(pchStr,iLen, "%d" ,iRandValue);
printf ( "\n====%s====\n" ,pchStr);
}
return ;
}
int main()
{
char str[20];
memset (str,0, sizeof (str));
make_rand_str(str, sizeof (str),10); // 10个随机数
// printf("\n====%s====\n",str);
return 0;
}
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以上为个人经验,希望能给大家一个参考,也希望大家多多支持服务器之家。如有错误或未考虑完全的地方欢迎留言讨论,望不吝赐教。
原文链接:https://www.cnblogs.com/whwywzhj/p/10578307.html