C # And C ++

I just converted a program from c # To c ++. Therefore, I have a basic understanding of c # And c ++. Of course, there are too many things in the book that I will not mention, and many underlying things cannot be felt during development. For example, CLR. Just look at the syntax. Haha.

1. C # It is much easier to use arrays than C ++, especially when the subscript is not a constant but determined only when the program is running. For example, a two-dimensional array, in C ++, we have to apply for the following space twice:

Int ** p = NULL;

P = new int * [width];

For (int I = 0; I <width; I ++)

P [I] = new int [height];

But in c #, you only need int [,] p = new int [width] [height]; a statement.

2. In terms of file read/write, c ++ is still much more powerful. It may be because c # does not have the pointer concept. Therefore, the c # File Read and Write function is basically readbyte (); readline (), either one byte to read, or read as a string, and then you parse the string. Binary read/write binaryreader and binarywriter provide readint32 (), readsingle (), and so on, but the file must be a binary file. Therefore, if we hand-written a text document, some data separated by spaces, including characters, floating point numbers, and so on, we cannot do the same as the original C ++,

Scantf ("% d % f ...", D, f );

I thought it was inconvenient to use this.

3. Function overload. C # is more convenient than C ++. For example, if I write a function swap () that exchanges two variables, if it is C ++, it may need swap (int, int), sway (float, float), etc, or use the template. C #, because all data types are inherited from objects, it is enough to use a function swap (object, object. Of course, there will be some box and unbox operations that affect efficiency, but for me writing programs, I still feel much more convenient.

4. For the "C # variable must be assigned before it is used", I feel that it may cause some inconvenience. For example, assign a value to a variable in a condition statement, even if the program writer can ensure that his or her condition statement is successful, the variable must be assigned a value. However, C # may encounter errors. You must explicitly assign values outside the Condition Statement.

E. g Point p;

If (a = 1)

P = new Point ();

....

Even if you can ensure that a = 1 is true, C # requires that p = new Point () be placed out of the Condition Statement. Of course, there is nothing very inconvenient in this example. I cannot think of a good example at the moment. Sorry.