FileStream获取错误算术运算导致溢出

Question

I try to get bytes from file using this method

byte[] b1;
using (var fs = new FileStream(path, FileMode.Open, FileAccess.Read))
                {
                    b1= new byte[fs.Length];
                    int bytesRead = fs.Read(b1, 0, b1.Length);
                } 

but when i test it with file size = 4.9GB its throw exception say Arithmetic operation resulted in an overflow.

Answer 1

A byte[] can only have a maximum length of 2,147,483,647. Trying to create a btye[] that is longer than that will cause an OverflowException to be thrown

Answer 2

Basically, to check for arithmetic overflow exceptions in your solution you can set in your Project Properties -> Build -> Advanced -> Check for arithmetic overflow/underflow

But this property may cause performance issues at runtime. Therefore, one must be careful in using integers. As pointed above, your file size is 4.9GB so 4,900,000,000 > 2,147,483,647 (which you can check using Int32.MaxValue in c#)

To resume, when you're using filestream you must check your input parameters and expect these type of issues by adding some try catch blocks to avoid unhandled exceptions that result in a bad experience for the user.