Hi - it's the student again!<br>Here's my code & the errors that I keep getting. I've tried several different fixes and consulted numerous texts. Please explain why this is not working and how it can be fixed... thank you!<br><br>struct structure <br>{<br> char FName[19];<br> char LName[19];<br> char Address[51];<br>};<br><br>structure entry[50]; <br>structure tempname;<br><br><br>void Alphabetize(int structcount, structure &entry)<br>{<br><br> <br> for (int count=0;count<(structcount-1);count++)<br> {<br> if (strcmp(entry.LName[count], entry.LName[count+1]) < 0)<br> {<br> strcpy(tempname, entry.LName[count]);<br> strcpy(entry.LName[count], entry.LName[count+1]);<br> strcpy(entry.LName[count+1], tempname);<br><br> }<br> }<br>}<br><br><br>'strcmp' : cannot convert parameter 1 from 'char' to 'const char *'<br>Conversion from integral type to pointer type requires reinterpret_cast, C-style cast or function-style cast<br><br>'strcpy' : cannot convert parameter 1 from 'struct structure' to 'char *'<br> No user-defined-conversion operator available that can perform this conversion, or the operator cannot be called<br><br>'strcpy' : cannot convert parameter 1 from 'char' to 'char *'<br>Conversion from integral type to pointer type requires reinterpret_cast, C-style cast or function-style cast<br>
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strcpy/strcmp problems 1
- Thread starter Dena
- Start date
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1
- #2
Karl Blessing
Programmer
strcmp assumes you are passing an array of characters, not a single character. if You want to compare two single characters if 'a' = 'a' would do fine, but it appears you are trying to check if its smaller or whatnot, so try using an amperstand & , which means Address of. because it is expecting a pointer to a string (which is the only way to get entry into a multicharacter string)<br><br>also Temperturename is not a string, its a struct as you declared it as<br><br>if (strcmp(&entry.LName[count], &entry.LName[count+1]) < 0)<br>{<br>//next line isnt a string, fix it or change its type<br>strcpy(tempname, entry.LName[count]);<br><br>strcpy(&entry.LName[count], entry.LName[count+1]);<br>strcpy(&entry.LName[count+1], tempname);<br><br>}<br><br>I dont know how you plan to use tempname, but you cant make a structure into a string <p>Karl<br><a href=mailto:kb244@kb244.8m.com>kb244@kb244.8m.com</a><br><a href= </a><br>Experienced in , or have messed with : VC++, Borland C++ Builder, VJ++6(starting),VB-Dos, VB1 thru VB6, Delphi 3 pro, Borland C++ 3(DOS), Borland C++ 4.5, HTML, ASP(somewhat), QBasic(least i didnt start with COBOL)
Karl Blessing
Programmer
but wouldnt that still identify the parameters as a single character rather than an array of strings. <p>Karl<br><a href=mailto:kb244@kb244.8m.com>kb244@kb244.8m.com</a><br><a href= </a><br>Experienced in , or have messed with : VC++, Borland C++ Builder, VJ++6(starting),VB-Dos, VB1 thru VB6, Delphi 3 pro, Borland C++ 3(DOS), Borland C++ 4.5, HTML, ASP(somewhat), QBasic(least i didnt start with COBOL)
- Thread starter
- #5
Ok, I've moved the [count] to the right location and now I get a totally new set of errors. Two for each strcmp/strcpy in the program. I discussed it with a grad student at school who said that I needed to use the new command. Now if I declare a structure, aren't I asking for memory? Would I be repeating myself if I did:<br><br>structure entry[50]; // declaring type 'structure' with variable 'entry' as an array of<br> 50 elements.<br><br>entry = new structure[50]; // allocating memory for a variable 'entry' of 50<br> elements of the type 'structure' <br><br>The following statement is just one of many strcmp/strcpy commands that all give me the same following error:<br><br>if (strcmp(entry[count].FName, "q"
== 0) <br> <br><br>error C2676: binary '[' : 'struct structure' does not define this operator or a conversion to a type acceptable to the predefined operator<br>error C2228: left of '.FName' must have class/struct/union type<br><br>
== 0) <br> <br><br>error C2676: binary '[' : 'struct structure' does not define this operator or a conversion to a type acceptable to the predefined operator<br>error C2228: left of '.FName' must have class/struct/union type<br><br>
Karl Blessing
Programmer
A structure does not allocate memory, but any new objects based on that structure does. For example the declaration of a structure or a class, only defines its skeleton, what it looks like, its a snapshot, then you declare an object.<br><br>the first one where you just did <br>StructureName StructObject[50];<br>declares an array of structure objects, or I like to call them nodes sometimes.<br>the next line, if you declared entry as<br>StructureName *entry;<br>then entry = new structurename[50];<br><br>would point the pointer to the new object in memory which is an array of 50 struct types.<br><br>for example<br><br>struct MyStruct<br>{<br>int Age;<br>};<br><br>MyStruct.Age = 12 //CANT DO THIS , MyStruct doesnt really exist it only exist as a Type which defines how the 'MyStruct' is setup<br>If you want to use this , declare an object<br><br>MyStruct MyObj;<br><br>MyObj.Age = 12; //Now this will work<br><br>or you can declare the object(or objects) right after the declaration<br><br>struct MyStruct<br>{<br>int Age;<br>}myObj[50];<br>(multiples can be }MyObj[50],*entry,SimpleObj; )<br><br>Just making sure you understood how a structure is setup.<br>in order to use the new operator the object you are assigning it to must be a pointer, and whenever you use pointers you cant use . to goto member functions(unless you dereference the type first) but instead using -> for example<br>entry->FName;<br> <p>Karl<br><a href=mailto:kb244@kb244.8m.com>kb244@kb244.8m.com</a><br><a href= </a><br>Experienced in , or have messed with : VC++, Borland C++ Builder, VJ++6(starting),VB-Dos, VB1 thru VB6, Delphi 3 pro, Borland C++ 3(DOS), Borland C++ 4.5, HTML, ASP(somewhat), QBasic(least i didnt start with COBOL)
You do not need the new operator, you already declared an array of type entry with structure entry[50];<br>And since it is not a pointer you do not need new.<br><br>if(strcmp(entry[index].LName,"q"==0)<br>should be true if LName = "q".<br>if you are looking for the first letter if LName you would <br>use <br>if(entry[index].LName[0]== 'q')// this would be true if LName[0] was 'q'.<br>If this doesnt help, send me the new code and I will look it over,<br><br>Tom.<br><A HREF="mailto:TMclaug2@optonline.net">TMclaug2@optonline.net</A><br>
==0)<br>should be true if LName = "q".<br>if you are looking for the first letter if LName you would <br>use <br>if(entry[index].LName[0]== 'q')// this would be true if LName[0] was 'q'.<br>If this doesnt help, send me the new code and I will look it over,<br><br>Tom.<br><A HREF="mailto:TMclaug2@optonline.net">TMclaug2@optonline.net</A><br> - Status