Thread: Help with error Message?: error C2440: '=' : cannot convert from 'int' to 'string'

I'm assuming that getLine() returns a string and you are trying to compare that with an int in your if statement and the compiler has no standard way of doing that. It's like comparing a house to a book.

What is the function signature of GetLine()?

EDIT: ALSO note that your if comparison's are wrong, '=' is an assignment operator, '==' is an equality check.

1) What is the return type of GetLine()?

2) change your if clauses so that = is replaced by ==.

if(x = 3) will always be true because you are not comparing x to 3, you are assigning the value 3 to x and this evaluates to true.

if(x == 3) is what you want.

Originally Posted by Nothing595

Yea, I had == before, but I got 3 more error messages saying: error C2040: '==' : 'string' differs in levels of indirection from 'int'

That's why I got rid of them.

Keep up the good work then!

ROFL

Not very sure how your GetLine function works. Assuming that it returns a proper string. You are assigning the returned string from GetLine() to Choice. Remember there is no datatype called string in C. Its only in C++. Which means the following statement is invalid

Code:

string choice;

Moving further, the Choice is checked to be any one of those dimensions. But you’re using assignment operator to compare string. This is not correct. In C you cant compare string using '==' operator. Using strcmp function to compare two string.

Code:

if( GetLine()=Box)

should have been

if( choice == Box) // if c+ , if Box = "Box"

if( strcmp( choice, "Box" )  == 0 ) // in C

Ssharish

Code:

printf("The Volume is : %s\n",Volume1);

Find the problem with above line and correct it; correct all the other problems starting with the first one you know how to fix.

Hint: What type is Volume1?

If you do not see the problem; read up on the printf method of printing different variable types.

What type should be used for Volume2? Is int the correct type?



Tim S.

Should some what look like this

Code:

char *choice;

      if( strcmp(choice,"Box") == 0 )
      {
        printf("Enter Width:");
	    w=GetInteger();
        printf("Enter Height:");
        h=GetInteger();
        printf("Enter Length:");
        l=GetInteger();
        Volume1=w*h*l;
        printf("The Volume is : %s\n",Volume1);
      }
      else if( strcmp(choice, "Cylinder") == 0 )
      {
        printf("Enter Radius");
        r=GetInteger();
        printf("Enter Height");
        s=GetInteger();
        Volume2=3.14*r*r*h;
        printf("The Volume is: %s",Volume2);
      }
      else if ( strcmp(choice,"Cube") == 0 )

I haven't compiled the code. Your code indentation is horriable. If you look for any help on this form. You should first learn how to indent your code properly.

ssharish

The first thing to work on is datatype string and the functioin GetLine. Are they working as expected?

ssharish