例如从一个输入框输入:31 32 33 34字符串，在程序中转换成十六进制0x31 0x32 0x33 0x34
应用：如求数据的crc码，先从输入框输入十六进制数据，需将字符串转换成十六进制，再对此序列数据进行crc计算，再将数据和crc码输出到输出框中
#include "mainwindow.h"#include "ui_mainwindow.h"#include <QArrayData>#include <QDebug>#define crc_mul 0x1021 //生成多项式unsigned int msg_crc(unsigned char *ptr, unsigned char len){unsigned char i;unsigned int crc=0;while(len-- != 0){for(i=0x80; i!=0; i>>=1){if((crc&0x8000)!=0){crc<<=1;crc^=(crc_mul);}else{crc<<=1;}if((*ptr&i)!=0){crc ^= (crc_mul);}}ptr ++;}return (crc);}MainWindow::MainWindow(QWidget *parent): QMainWindow(parent), ui(new Ui::MainWindow){ui->setupUi(this);connect(ui->inputButton,SIGNAL(clicked()),this,SLOT(calc_and_display_crc()));}MainWindow::~MainWindow(){delete ui;}void string_to_hex(QString hex,QByteArray &qbyte){hex=hex.trimmed();QStringList sl=hex.split(" ");foreach(QString s,sl){if(!s.isEmpty())qbyte.append((char)s.toInt(0,16)&0xFF);}}void MainWindow:: calc_and_display_crc(void){QByteArray aa,bb;QString str0;QString str1;bool ok;unsigned char crcBuf[50];unsigned short crc;int i;str0 = ui->inputDataEdit->text();string_to_hex(str0,aa);for(i=0;i<aa.size(); i++){crcBuf[i] = aa[i];}crc = msg_crc(crcBuf,i);str1 = QString::number(crc);qDebug()<<str1;aa[i] = crc>>8;aa[i+1] = crc &0x00ff;//aa = str0.toLocal8Bit();ui->disQtext->setText(aa.toHex(' '));}
效果：
