Databases
StackOverflow2013
Postsdbo
POFile I/O Code in C++
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POFile I/O Code in C++
    primarykey
    data
    text
    <p>So I've been up for a long time now and maybe thats why I can't figure this out. But my code here will work only on the first execution, i.e., since there is a menu with about 4 options, it will work only for the one that is selected first. When the do while loop kicks in and the menu is displayed again, no matter what you select, it keeps re displaying the menu. I have analyzed the do while loop but am pretty sure there aren't any problems with that. I've only recently started learning about File I/O so maybe there's something I missed. Any help would be really appreciated. Thanks.</p> <p>Here's the code:</p> <p><strong>Phonebook.h</strong></p> <pre><code>#include &lt;iostream&gt; #include &lt;fstream&gt; #include &lt;cstdlib&gt; #include &lt;string&gt; using namespace std; class Phone { public: void display_phonebook(ifstream&amp; in_stream);// phonebook is the text file void display_backup(string a[], int size);// backup copy is a string array void datacopy(ifstream&amp; in_stream, string a[]);// to copy the phonebook to the array int numberOfLines(ifstream&amp; in_stream);// to check number of lines in the text file }; </code></pre> <p><strong>Phonebook.cpp</strong></p> <pre><code>#include &lt;iostream&gt; #include &lt;fstream&gt; #include &lt;cstdlib&gt; #include &lt;string&gt; #include "Phonebook.h" using namespace std; void Phone::datacopy(ifstream&amp; in_stream, string a[]) { int i=0; while(in_stream.good()) { string line; getline(in_stream, line); a[i]=line; i++; } int s=i; for(int x=0;x&lt;s;x++) { cout&lt;&lt;a[x]&lt;&lt;endl; } } int Phone::numberOfLines(ifstream&amp; in_stream) { int count=0; while(!in_stream.eof()) { string line; getline(in_stream, line); count++; } return count; } void Phone::display_phonebook(ifstream&amp; in_stream) { while(!in_stream.eof()) { string line; getline(in_stream, line); cout&lt;&lt;line&lt;&lt;endl; } } void Phone::display_backup(string a[], int size) { for(int i=0;i&lt;size;i++) { cout&lt;&lt;a[i]&lt;&lt;endl; } cout&lt;&lt;endl; } </code></pre> <p><strong>main.cpp</strong></p> <pre><code>#include &lt;iostream&gt; #include &lt;fstream&gt; #include &lt;cstdlib&gt; #include &lt;string&gt; #include "Phonebook.h" using namespace std; int main() { Phone p; int size=0; ifstream fin; ofstream fout; char file[50], ch; string backup[50]; int flag=0; do { cout&lt;&lt;"Enter the name of the file: "&lt;&lt;endl; cin&gt;&gt;file; fin.open(file); cout&lt;&lt;endl; if(fin.fail()) { cout&lt;&lt;"File not found!"&lt;&lt;endl&lt;&lt;endl; cout&lt;&lt;"Try Again? (Y/N)"&lt;&lt;endl; cin&gt;&gt;ch; if(ch=='N' || ch=='n') { cout&lt;&lt;"Terminating..."&lt;&lt;endl; system("PAUSE"); exit(1); } } else { flag=1; } } while((ch=='Y' || ch=='y') &amp;&amp; flag==0); cout&lt;&lt;"Success! File Opened"&lt;&lt;endl&lt;&lt;endl; int choice; do { cout&lt;&lt;"1 - Display phonebook"&lt;&lt;endl; cout&lt;&lt;"2 - Display backup copy"&lt;&lt;endl; cout&lt;&lt;"3 - Update backup copy"&lt;&lt;endl; cout&lt;&lt;"4 - Exit"&lt;&lt;endl; cout&lt;&lt;"Enter your choice: "; cin&gt;&gt;choice; if(choice==1) { p.display_phonebook(fin); } else if(choice==2) { size=p.numberOfLines(fin); p.display_backup(backup, size); } else if(choice==3) { p.datacopy(fin, backup); } } while(choice!=4); fin.close(); fout.close(); system("PAUSE"); return 0; } </code></pre>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USdmckee
    1. USPulkit2692
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    3. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. POFile I/O Code in C++
      1. This table or related slice is empty.
      1. VTUpMod
    1. COGenerally an enormous code dump like this is not the way to get help from Stack Overflow. Surely you can pare this down to a minimal example that shows the problem. And if you solve it while you're doing that, then good for you!
      singulars
      1. POFile I/O Code in C++
      1. USdmckee
    2. COWhich while loop is troubling you? I counted 5 in your code.
      singulars
      1. POFile I/O Code in C++
      1. USjrok
    3. CO@Stencil @jrok: He means the do while loop with the literal `"1 - Display phonebook"`. The direct cause is the stream got in a bad state, but it's not immediately obvious _why_ it's in a bad state.
      singulars
      1. POFile I/O Code in C++
      1. USMooing Duck
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload