for 循环不会从 i = 0 开始
for loop won't begin at i = 0
//write_db_iec(writer_ob1.get_vector_db_timer()[0]);
for (int i = 0; i < writer_ob1.get_vector_db_timer().size(); i++) {
write_db_iec(writer_ob1.get_vector_db_timer()[i]);
}
是否有任何可能性,直接从i = 1开始?第一个元素(i = 0)可访问并包含元素。
[编辑]:我希望循环从i = 0开始。但是它失败了。
以下是函数write_db_iec:
void write_db_iec(db_iec db_timer) {
writer_file.open(writer_file_location, std::ios::app);
if (writer_file.is_open()) {
//NOTICE
std::cout << "Begin writing db timer-n";
//COMMENT
writer_file << "//DATA BLOCK FOR TIMER -n";
writer_file << "//FOR " << db_timer.get_db_iec_timer().get_name() << "n";
//HEADER
writer_file << "DATA_BLOCK " << db_timer.get_db_name() << "n"
<< "{ S7_Optimized_Access := 'FALSE'}n"
<< "NAME : " << db_timer.get_db_iec_timer().get_type() << "n"
<< "VERSION : 0.1n";
//RELATED FB
writer_file << "BEGINn"
<< "END_DATA_BLOCKnnn";
//CLOSE FILE
writer_file.close();
}
else {
writer_status = false;
std::cout << "Error on writing timer DBn";
std::cout << "Timer DB Name : " << db_timer.get_db_iec_timer().get_name() << "n";
}
}
[添加]:ob1类:
class ob1 {
private:
std::vector<std::string> ob1_var_temp;
std::vector<fb> ob1_fb;
std::vector<db> ob1_db;
std::vector<db_iec> ob1_db_timer;
//load var temp for ob1, should be called before writer
void load_var_temp() {
//not important
}
public:
ob1() { load_var_temp(); }
ob1(fb fb1) {
ob1_fb.push_back(fb1);
load_var_temp();
}
std::vector<fb> &get_vector_fb() {
return ob1_fb;
}
std::vector<db> &get_vector_db() {
return ob1_db;
}
std::vector<db_iec> &get_vector_db_timer() {
return ob1_db_timer;
}
std::vector<std::string> &get_vector_var_temp() {
return ob1_var_temp;
}
//to generate db, should be called before writer
void generate_db(std::vector<fb> functionblock) {
if (functionblock.size() > 0) {
for (int i = 0; i < functionblock.size(); i++) {
ob1_db.push_back(functionblock[i]);
}
}
}
//overloaded function from generate db
void generate_db() {
std::vector<fb> functionblock = ob1_fb;
if (functionblock.size() > 0) {
for (int i = 0; i < functionblock.size(); i++) {
ob1_db.push_back(functionblock[i]);
}
}
}
//to generate db timer, should be called before writer
void generate_db_timer(std::vector<fb> functionblock) {
for (int i = 0; i < functionblock.size(); i++) {
if (functionblock[i].get_timer().size() > 0) {
ob1_db_timer.push_back(functionblock[i].get_timer()[i]);
}
}
}
//to generate db timer, should be called before writer, overloaded function
void generate_db_timer() {
std::vector<fb> functionblock = ob1_fb;
for (int i = 0; i < functionblock.size(); i++) {
if (functionblock[i].get_timer().size() > 0) {
for (int j = 0; j < functionblock[i].get_timer().size(); j++) {
ob1_db_timer.push_back(functionblock[i].get_timer()[j]);
}
}
}
}
//to add fb into ob1
void add_fb(fb functionblock) {
ob1_fb.push_back(functionblock);
}
};
它具有db_iec类的向量。这是db_iec类:
// data block for iec timer
class db_iec {
private:
timer db_iec_timer;
std::string db_name;
public:
db_iec() {}
db_iec(timer iec_timer) : db_iec_timer{ iec_timer } {}
std::string &get_db_name() {
return db_name;
}
timer &get_db_iec_timer() {
return db_iec_timer;
}
};
和最后一个,我声明自己的功能,然后将其称为for loop
void analyse_ob1() {
writer_file.open(writer_file_location);
if (writer_file.is_open()) {
writer_file << "///////////////////////////////////////////////////////////////////////////////////////n";
writer_file << "//This is an automatically generated coden";
time_t theTime = time(NULL);
struct tm *aTime = localtime(&theTime);
int day = aTime->tm_mday;
int month = aTime->tm_mon + 1; // Month is 0 - 11, add 1 to get a jan-dec 1-12 concept
int year = aTime->tm_year + 1900;
int second = aTime->tm_sec;
int minute = aTime->tm_min;
int hour = aTime->tm_hour;
writer_file << "//Date : " << day << "." << month << "." << year << "n";
writer_file << "//Time : " << hour << ":" << minute << ":" << second << "n";
writer_file << "///////////////////////////////////////////////////////////////////////////////////////nnn";
}
//write_db_iec(writer_ob1.get_vector_db_timer()[0]);
for (int i = 0; i < writer_ob1.get_vector_db_timer().size(); i++) {
//writer_file.open(writer_file_location, std::ios::app);
//writer_file << "DB_Number : " << i << "n";
write_db_iec(writer_ob1.get_vector_db_timer()[i]);
}
for (int i = 0; i < writer_ob1.get_vector_fb().size(); i++) {
write_fb(writer_ob1.get_vector_fb()[i]);
write_db(writer_ob1.get_vector_db()[i]);
}
write_ob1();
}
};
[已解决]:我必须先关闭文件(writer_file.close()),然后才调用函数write_db_iec()。谢谢您的所有答案。
问题不是for循环,这是可以肯定的。除非writer_ob1.get_vector_db_timer().size() == 0
,否则将使用i = 0
执行循环主体。否则根本不会执行循环主体。
确保从writer_ob1.get_vector_db_timer()
返回的向量确实包含您期望的元素。
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