c语言如何将字符串强制转换为整型？如"162837"转化为162837 C语言中 字符串如何转为整型数值
C\u8bed\u8a00\u5b57\u7b26\u4e32\u7c7b\u578b\u8f6c\u6362\u4e3a\u6574\u578b\u6216\u6d6e\u70b9\u600e\u4e48\u505a\u5927\u6570\u7684\u5f62\u5f0f\u8f6c\u6362\uff0c\u9700\u8981\u81ea\u5df1\u5b9e\u73b0\u4e00\u4e2a\u6269\u5c55\u65b9\u5f0f\u3002
\u524d\u4e24\u5929\u521a\u5e2e\u53e6\u5916\u4e00\u4e2a\u4eba\u5b9e\u73b0\u4e86\u4e00\u4e2a100\u4f4d\u4ee5\u5185\u5341\u8fdb\u5236\u6570\u5b57\u7b26\u8f6c16\u8fdb\u5236\u7684\u5b9e\u73b0\uff1a
#include #include #include #define isdigit(c)('0' 0){ to_div = rem*10 + *div; quo[quo_size] = to_div/16; rem = to_div%16; quo_size++; num_size--; div++; } memcpy(big_num,quo,quo_size); *p_size=quo_size; free(quo); return rem;}int main(){ char input[MAX_DIGI_NUM] = {0}; char num[MAX_DIGI_NUM+1] = {0}; char hex[MAX_DIGI_NUM+1] = {0}; int i,num_size,result; printf("input Dec num:"); scanf("%s",input); memcpy(num,input,MAX_DIGI_NUM); i = num_size = strlen(num); if(i >= MAX_DIGI_NUM){ printf("input num is too big!\n"); return 0; } while(i--){ if(!isdigit(num[i])){ printf("input num is not valid!\n"); return 0; } num[i] = atoi(&num[i]); }\u3000\u3000char *tmp = &hex[MAX_DIGI_NUM];\u3000\u3000while(num_size)\u3000\u3000{\u3000\u3000result = _div_16(num, &num_size);\u3000\u3000tmp--;\u3000\u3000if(result <= 9)\u3000\u3000*tmp = 0x30 + result;\u3000\u3000else\u3000\u3000*tmp = 0x60 + result-9;\u3000\u3000} printf("Hex num is 0x%s\n",tmp);}
\u5728C\u8bed\u8a00\u4e2d\u5c06\u5b57\u7b26\u4e32\u8f6c\u5316\u6210\u6574\u578b\u6709\u4e24\u79cd\u65b9\u6cd5\u3002
1 \u7528atoi\u51fd\u6570\u3002
atoi\u7684\u529f\u80fd\u5c31\u662f\u5c06\u5b57\u7b26\u4e32\u8f6c\u4e3a\u6574\u578b\u5e76\u8fd4\u56de\u3002\u5176\u58f0\u660e\u4e3a
int atoi(char *str);
\u6bd4\u5982atoi("1234");\u4f1a\u8fd4\u56de\u6574\u578b1234\u3002
\u8981\u8c03\u7528atoi,\u9700\u8981\u5f15\u7528\u5934\u6587\u4ef6stdio.h
2 \u7528sscanf\u3002
sscanf\u4e0e\u6807\u51c6\u683c\u5f0f\u5316\u8f93\u5165\u51fd\u6570scanf\u7c7b\u4f3c\uff0c\u4e0d\u8fc7\u6e90\u5e76\u975e\u662f\u6807\u51c6\u8f93\u5165\uff0c\u800c\u662f\u5b57\u7b26\u4e32\u3002
\u7528sscanf\u53ef\u4ee5\u5904\u7406\u66f4\u590d\u6742\u7684\u5b57\u7b26\u4e32\u3002
\u6bd4\u5982\u5b57\u7b26\u4e32char * str = "a=1, b=2";
\u5b9a\u4e49int a,b;\u540e
\u53ef\u4ee5\u7528
sscanf(str,"a=%d, b=%d",&a,&b);
\u6765\u5c06a,b\u503c\u63d0\u53d6\uff0c\u8ba1\u7b97\u540e\uff0ca=1, b=2\u3002
\u8981\u4f7f\u7528sscanf\u540c\u6837\u9700\u8981\u5f15\u7528\u5934\u6587\u4ef6stdio.h\u3002
实例参考：
#include <stdio.h>
#include <stdlib.h>
char x[10]={'1','6','2','8','3','7','\0'};
int main(void)
{
int y=atoi(x);
printf("This is a string.\n");
printf("%s\n", x);
printf("This is a number.\n");
printf("%d\n", y);
system("pause");
return 0;
}
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