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#include <stdio.h> int main(void) { FILE *fp; //打开文件前必须要定义FILE*型指针变量 int lines = 0; char name[128]; double height, weight; double hsum = 0, wsum = 0; if((fp = fopen("hw.dat","r")) == NULL) printf("afile does not exist! "); else { while(fscanf(fp, "%s%lf%lf", name, &height, &weight) == 3) // fscanf函数用于读取文件,fscanf函数和scanf函数相似,多了一个参数,即流(指针)。 //fscanf函数的返回值为成功赋值的项目 { printf("%-8s%8.3f%8.3f ", name, height, weight); lines++; hsum += height; wsum += weight; } puts(" ============================ "); printf("average: %8.3f%8.3f ", hsum/lines, wsum/lines); fclose(fp); } return 0; }
c语言中读取文件的函数为fscanf函数,fscanf函数与scanf函数相似,多了一个参数,即流(指针), fscanf函数的返回值为成功赋值的项目数。