You may not know the switch

One:

Int I = 0;

Switch (I)
{
Case 0:
Console. WriteLine ("0 ");
Case 1:
Console. WriteLine ("1 ");
Break;
}

// Here, you want to execute

// Console. WriteLine ("0"), and then "fall through" to the lower layer to execute Case 1.

// However, "fall through" is not allowed in C. Unless none of the "case 0" statements exist.

However, you can use the goto statement to implement "fall through"

 

Int I = 0;
Switch (I)
{
Case 0:
Console. WriteLine ("0 ");
Goto case 1;
Case 1:
Console. WriteLine ("1 ");
Break;
} In C #, every case xxx is a tag, so you can use the goto statement to redirect.

 

Two:
 

 

Here, the default statement does not do anything, but does not add break;

The prompt is as follows:

 

C # Strictly control that the branches of each Switch are not allowed to run through ("fall through"). For example, sometimes you may look like the following:

 

This statement is completely legal.

 

Three:
Sometimes you define variables in case, but the variables may have the same name, for example:

 

Two identical variables, y, are defined in case 0 and case 1. The Compiler prompts the following error:

 

To solve this problem, add "{}" to convert the Case statement into a BLOCK statement.

 

Of course, there is also an unknown solution, as shown below:

 

 

 

Four:
Suppose you have a method M and the code is as follows:

Int M (bool B)
{
Switch (B)
{
Case true: return 1;
Case false: return 0;
}
} It is obvious that B has only two values, one being true and the other being false, but the compiler fails. The prompt is:

 

The compiler considers that every switch structure can be executed and does not execute it. However, method M must have an int return value, so the compiler prompts an error.

The solution to this problem is also simple:

Int M (bool B)
{
Switch (B)
{
Case true: return 1;
Default: return 0;
}
} Or:

Int M (bool B)
{
Return B? 1: 0;
}