1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
|
// Program to read a CSV file containing company items into an array of structures
//
// Author:
//
// date: 10/18/20
//
//
#include <stdio.h>
#include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include <cstdlib>
using namespace std;
#define DEBUG 1
#define MAX_ITEMS 4
struct Item {
int partNumber;
string partName;
int partQuantity;
double price;
};
bool openFileIn(fstream &, string);
int getItems(fstream &, Item *);
int showItems(Item *);
void split(const string&, char , vector<string>& );
int main()
{
fstream dataFile; // data file
Item *items = new Item[MAX_ITEMS]; // dynamically allocate student records
if (openFileIn(dataFile, "widgets.dat"))
{
// get Student data from file into array
getItems(dataFile, items);
dataFile.close();
showItems(items);
}
else
cout << "File open error!" << endl;
return 0;
}
//***********************************************************
// Definition of function openFileIn. Accepts a reference *
// to an fstream object as an argument. The file is opened *
// for input. The function returns true upon success, false *
// upon failure. *
//***********************************************************
bool openFileIn(fstream &file, string name)
{
file.open(name.c_str(), ios::in);
if (file.fail())
return false;
else
return true;
}
/*
* getStudent data one line at a time from
* the file. Parse the line using ',' as delimiter.
* Save data read to a Item record pointed to
* by s_ptr;
*/
int getItems(fstream &file, Item *s_ptr)
{
string input; // To hold file input
int count = 0;
// Read item data from file using ',' as a delimiter.
while (count < MAX_ITEMS && getline(file, input)) {
// vector to hold the tokens.
vector<string> tokens;
// Tokenize str1, using ' ' as the delimiter.
split(input, ',', tokens);
/*
* copy the tokens to the item record
*/
s_ptr->partNumber = atoi(tokens.at(0).c_str());
s_ptr->partName = tokens.at(1);
s_ptr->partQuantity = tokens.at(2);
s_ptr->price = atof(tokens.at(3).c_str());
count++;
s_ptr++;
cout << endl;
}
}
/*
* show all items
*/
int showItems(item *s_ptr)
{
/* Display the headings for each column, with spacing and justification flags */
printf("%-8s%-30s%-10s%-8s\n", "partNumber", "partName", "partQuantity", "price");
// Read item data from file using ',' as a delimiter.
for (int i = 0; i < MAX_ITEMS; i++) {
if (s_ptr->partNumber != 0) {
printf("%-8d%-30s%-10s%-2.2f\n",
s_ptr->partNumber,
s_ptr->partName.c_str(),
s_ptr->partQuantity.c_str(),
s_ptr->price);
s_ptr++;
}
/* If the id field is zero, then we reached the last student, break
* out of the for loop.
*/
else
break;
}
}
//**************************************************************
// The split function splits s into tokens, using delim as the *
// delimiter. The tokens are added to the tokens vector. *
//**************************************************************
void split(const string& s, char delim, vector<string>& tokens)
{
int tokenStart = 0; // Starting position of the next token
// Find the first occurrence of the delimiter.
int delimPosition = s.find(delim);
// While we haven't run out of delimiters...
while (delimPosition != string::npos)
{
// Extract the token.
string tok = s.substr(tokenStart, delimPosition - tokenStart);
// Push the token onto the tokens vector.
tokens.push_back(tok);
// Move delimPosition to the next character position.
delimPosition++;
// Move tokenStart to delmiPosition.
tokenStart = delimPosition;
// Find the next occurrence of the delimiter.
delimPosition = s.find(delim, delimPosition);
// If no more delimiters, extract the last token.
if (delimPosition == string::npos)
{
// Extract the token.
string tok = s.substr(tokenStart, delimPosition - tokenStart);
// Push the token onto the vector.
tokens.push_back(tok);
}
}
}
|
