字符串转整型(C语言)

字符串转整型(C语言)

second60 20180529

#include <stdio.h>
int str2int(const char* str)
{
    int temp = 0;
    const char* p = str;
    if(str == NULL) return 0;
    if(*str == '-' || *str == '+')
    {
        str ++;
    }
    while( *str != 0)
    {
        if( *str < '0' || *str > '9')
        {
            break;
        }
        temp = temp*10 +(*str -'0');
        str ++;
    }
    if(*p == '-')
    {
        temp = -temp;
    }
    return temp;
}

int main(int argc,char **argv)
{
    int n = 0;
    char str[7] = "-12345";
    n = str2int(str);
    printf("n=%d\n",n);
    getchar();
    return 1;
}