1 //-------------------------------------------1 2 #include<stdio.h> 3 #include<stdlib.h> 4 void main() 5 { 6 FILE *fp; 7 int x; 8 if((fp=fopen("f1.txt","w+"))==NULL)//打开（创建）文件为写入数据做准备 9 { 10 printf("Can't open this file!\n"); 11 exit(1); 12 } 13 printf("input x:"); 14 scanf("%d",&x); 15 fprintf(fp,"%6d",x);//将变量x中的值写入文件 16 fclose(fp);//关闭文件 17 18 if((fp=fopen("f1.txt","r+"))==NULL)//再打开文件为写入数据做准备 19 { 20 printf("Can't open this file!\n"); 21 exit(2); 22 } 23 fscanf(fp,"%d",&x);//由文件读出整数给变量x; 24 printf("%6d",x); 25 printf("\n"); 26 fclose(fp);//再关闭文件 27 } 28 //---------------------------------------------------------2 29 /* 30 打开文件函数fopen().关闭文件函数fclose(). 31 字符读取函数fgetc和fputc 32 字符串读取函数fgets和fputs 33 格式化读取函数fscanf和fprintf 34 数据块读取函数freed和fwrite 35 检测文件结束函数feof(),eof() 36 */ 37 #include<stdio.h> 38 #include<stdlib.h> 39 void main() 40 { 41 FILE *fp;//定义文件指针 42 char ch,filename[10];//定义字符变量和字符数组，字符数组用来放文件名 43 gets(filename);//接受来自键盘输入的文件名 44 if((fp=fopen(filename,"w"))==NULL)//打开文件并判断是否成功 45 { 46 printf("can not open file\n"); 47 exit(1);//打开文件失败结束过程，exit()函数在stdlib.h中 48 } 49 printf("Please input string:"); 50 while ((ch=getchar())!='#')//循环接受字符，并判断是否是结束符 51 fputc(ch,fp);//将字符写入文件 52 fclose(fp);//关闭文件 53 } 54 //-------------------------------------------3 55 #include"stdio.h" 56 #include<stdlib.h> 57 void main() 58 { 59 FILE *in,*out; 60 char ch,infile[10],outfile[10]; 61 scanf("%s",infile); 62 scanf("%s",outfile); 63 if((in=fopen(infile,"r"))==NULL) 64 { 65 printf("can not open infile\n"); 66 exit(1); 67 } 68 if((out=fopen(outfile,"w"))==NULL) 69 { 70 printf("cannot open outfile\n"); 71 exit(1); 72 } 73 while((ch=fgetc(in))!=EOF) 74 fputc(ch,out); 75 fclose(in); 76 fclose(out); 77 } 78 //-------------------------------------4 79 #include<stdio.h> 80 #include<string> 81 void main() 82 { 83 FILE *fp; 84 char string[81];// 85 if((fp=fopen("file1.txt","w"))==NULL) 86 { 87 printf("can't open file"); 88 exit(1); 89 } 90 while(strlen(gets(string))>0) 91 { 92 fputs(string,fp); 93 fputs("\n",fp); 94 } 95 fclose(fp); 96 if((fp=fopen("file1.txt","r"))==NULL) 97 { 98 printf("can't open file"); 99 exit(1); 100 } 101 while(fgets(string,81,fp)!=NULL)//while（!feof(fp)） 102 103 fputs(string,stdout);//将string指向的字符串输出到stdout(显示器)上 104 fclose(fp); 105 } 106 //--------------------------------------5 107 #include<stdio.h> 108 #include<string> 109 #define N 10 110 void main() 111 { 112 FILE *fp; 113 int i,x; 114 if((fp=fopen("f1.txt","w+"))==NULL) 115 { 116 printf("Can't open this file!\n"); 117 exit(1); 118 } 119 for(i=0;i<N;i++) 120 { 121 scanf("%d,&x"); 122 fprintf(fp,"%6d",x); 123 } 124 fclose(fp); 125 if((fp=fopen("f1.txt","r+"))==NULL) 126 { 127 printf("Can't open this file!\n"); 128 exit(2); 129 } 130 for(i=0;i<N;i++) 131 { 132 fscanf(fp,"%d",&x); 133 printf("%6d",x); 134 } 135 printf("\n"); 136 fclose(fp); 137 } 138 //-----------------------------------------------6 139 #include<stdio.h> 140 #include<string> 141 struct stu 142 { 143 int num; 144 char name[10]; 145 int score[3]; 146 }student; 147 void main() 148 { 149 int i; 150 FILE *fp; 151 if((fp=fopen("list1","ab"))==NULL) 152 { 153 printf("cannot open file\n"); 154 exit(1); 155 } 156 printf("student information:\n"); 157 printf("num:\n"); 158 scanf("%d",&student.num); 159 printf("name:\n"); 160 scanf("%s",&student.name); 161 printf("score1:\n"); 162 scanf("%d",&student.score[0]); 163 printf("score2:\n"); 164 scanf("%d",&student.score[1]); 165 printf("score3:\n"); 166 scanf("%d",&student.score[2]); 167 if(fwrite(&student,sizeof(struct stu),1,fp)!=1)//写一个学生数据块文件 168 printf("file write error:\n"); 169 fclose(fp); 170 } 171 //----------------------------------------------------7 172 #include<stdio.h> 173 #include<stdlib.h> 174 #define N 3 175 struct stu 176 { 177 int num; 178 char name[10]; 179 int score[3]; 180 }students[N]; 181 void main() 182 { 183 FILE*fp; 184 int i; 185 if((fp=fopen("list ","rb"))==NULL)//以读方式打开二进制文件 186 { 187 printf("cannot open file!\n"); 188 exit(1); 189 } 190 for(i=0;i<N;i++) 191 { 192 fseek(fp,i*sizeof(struct stu),0);//以起点为基准，按学生数据块移动位置指针 193 fread(&students[i],sizeof(struct stu),1,fp);//读出一个学生数据 194 printf("%d,%s, %d,%d\n",students[i].num,students[i].name),students[i].score[0],students[i].score[1],students[i].score[2];); 195 } 196 fclose(fp); 197 } 198 //-------------------------------------------8 199 #include"stdio.h" 200 main() 201 { 202 FILE *fp1,*fp2; 203 char c; 204 fp1=fopen("work1","r"); 205 fp2=fopen("f2.txt","w"); 206 while((c=getc(fp1))!=EOF) 207 putchar(c);//读出work1中的信息并写到屏幕上 208 rewind(fp1);//把文件的内部指针移到文件的开始处 209 while((c=fgetc(fp1))!=EOF)//读出work1中的信息并写入到f2中 210 fputc(c,fp2); 211 fclose(fp1); 212 fclose(fp2); 213 } 214 //-----------------------------------9 215 #include<stdio.h> 216 #include<stdlib.h> 217 #define N 3 218 struct stu 219 { 220 int num; 221 char name[10]; 222 int score[3]; 223 }student[N]; 224 void main() 225 { 226 FILE*fp; 227 int i; 228 for(i=0;i<N;i++) 229 { 230 printf("%d student information:\n"); 231 printf("num:\n"); 232 scanf("%d",&students[i].num); 233 printf("name:\n"); 234 scanf("%s",students[i].name); 235 printf("score1:\n"); 236 scanf("%d",students[i].score[0]); 237 printf("score2:\n"); 238 scanf("%d",students[i].score[1]); 239 printf("score3:\n"); 240 scanf("%d",students[i].score[2]); 241 } 242 if(fwrite(&students,sizeof(struct stu),N,fp)!=N) 243 printf("file write error\n"); 244 fclose(fp); 245 if((fp=fopen("list","rb"))==NULL) 246 { 247 printf("Can't open this file!\n"); 248 exit(1); 249 } 250 if(fread(&students,sizeof(struct stu),N,fp)!=N) 251 printf("file write error\n"); 252 for(i=0;i<N;i++) 253 { 254 printf("%d,%s, %d,%d,%d\n",students[i].num,students[i].name,students[i].score[0],students[i].score[1],students[i].score[2]); 255 } 256 fclose(fp); 257 } 258 //-------------------------------------------10 259 #include<stdio.h> 260 #include<stdlib.h> 261 #define N 3 262 struct stu 263 { 264 int num; 265 char name[10]; 266 int score[3]; 267 }students[N]; 268 void main() 269 { 270 FILE*fp; 271 int i; 272 for(i=0;i<N;i++) 273 { 274 printf("%d student information:\n"); 275 printf("num:\n"); 276 scanf("%d",&students[i].num); 277 printf("name:\n"); 278 scanf("%s",students[i].name); 279 printf("score1:\n"); 280 scanf("%d",students[i].score[0]); 281 printf("score2:\n"); 282 scanf("%d",students[i].score[1]); 283 printf("score3:\n"); 284 scanf("%d",students[i].score[2]); 285 } 286 if((fp=fopen("data.txt","w+"))==NULL) 287 { 288 printf("Can't open this file!\n"); 289 exit(1); 290 } 291 for(i=0;i<N;i++) 292 { 293 printf("%d,%s, %d,%d,%d\n",students[i].num,students[i].name,students[i].score[0],students[i].score[1],students[i].score[2]); 294 } 295 fclose(fp); 296 }