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POread objects from file
 

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  1. POread objects from file
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    <p>I have this code:</p> <pre><code>#include &lt;fstream&gt; #include &lt;iostream&gt; using namespace std; class Student { public: char FullName[40]; char CompleteAddress[120]; char Gender; double Age; bool LivesInASingleParentHome; }; int main() { Student one; strcpy(one.FullName, "Ernestine Waller"); strcpy(one.CompleteAddress, "824 Larson Drv, Silver Spring, MD 20910"); one.Gender = 'F'; one.Age = 16.50; one.LivesInASingleParentHome = true; ofstream ofs("fifthgrade.ros", ios::binary); ofs.write((char *)&amp;one, sizeof(one)); Student three; strcpy(three.FullName, "three Waller"); strcpy(three.CompleteAddress, "three 824 Larson Drv, Silver Spring, MD 20910"); three.Gender = 'M'; three.Age = 17; three.LivesInASingleParentHome = true; //ofstream ofs("fifthgrade.ros", ios::binary); ofs.write((char *)&amp;three, sizeof(three));*/ Student two; ifstream ifs("fifthgrade.ros", ios::binary); while(!(ifs.eof())){ ifs.read((char *)&amp;two, sizeof(two)); cout &lt;&lt; "Student Information\n"; cout &lt;&lt; "Student Name: " &lt;&lt; two.FullName &lt;&lt; endl; cout &lt;&lt; "Address: " &lt;&lt; two.CompleteAddress &lt;&lt; endl; if( two.Gender == 'f' || two.Gender == 'F' ) cout &lt;&lt; "Gender: Female" &lt;&lt; endl; else if( two.Gender == 'm' || two.Gender == 'M' ) cout &lt;&lt; "Gender: Male" &lt;&lt; endl; else cout &lt;&lt; "Gender: Unknown" &lt;&lt; endl; cout &lt;&lt; "Age: " &lt;&lt; two.Age &lt;&lt; endl; if( two.LivesInASingleParentHome == true ) cout &lt;&lt; "Lives in a single parent home" &lt;&lt; endl; else cout &lt;&lt; "Doesn't live in a single parent home" &lt;&lt; endl; cout &lt;&lt; "\n"; } return 0; } </code></pre> <p>When i read from file, the last object prints twice. What should I do?</p>
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    1. USJack Bonneman
    1. UScprogrammer
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    1. This table or related slice is empty.
    1. COWriting structures like this is not portable. It depends on host-specific packing, floating point representation, and all sorts of ugly stuff, and includes holes in the structure. You should write it in a serialized, normalized form.
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      1. USSeth Robertson
    2. CO@Seth: you are right. I think it is fair to say, this is most likely homework, and this is ok for the sample
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      1. USsehe
    3. CO@sehe: Train them up right before they have a chance to make mistakes like this in more serious projects.
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      1. USSeth Robertson
 

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