C # basic notes (Day 5 ),

C # basic notes (Day 5 ),

1. for Loop
Forward-order Loop
For + tab
For (int I = 0; I <length; I ++)

Inverted Loop
Forr + tab
For (int I = length-1; I> = 0; I --)

2. daffodils
This hundred-bit hundreds of cubes + Ten cubes + cubes = this hundred-bit
100 bits: num/
Ten: num % 100/10
Single digit: num % 10

3. parse type conversion
If convert fails to be converted, an exception is thrown.
It basically calls parse.

4.int. TryParse

Int. Tryparse is a method

Try to convert a string to the int type.

1 // set an int type num with the initial value 02 int num = 0; 3 // use the Bool type to receive and use TryParse to try to convert "123abc" to the int type and save the Conversion Result to num. 4 bool B = int. tryParse ("123abc", out num); 5 // If the conversion is successful, B is true. If the conversion fails, B is false6 Console. writeLine (B); 7 // The converted value is successfully converted, and the conversion failed is the initial value of num 8 Console. writeLine (num); 9 Console. readKey ();

 

6. continue
Continue is generally used in combination with If
When a condition is met, return to the cyclic condition to judge
Difference from break
Continue: You can choose to continue or not execute the loop. execution or not execution depends on whether the loop condition is true or not.
Break: jump out of the loop directly

7. Prime Number/prime number
The number that can only be divided by 1 and the number itself. The minimum prime number is 2.

8. Ternary expressions
Syntax:
Expression 1? Expression 2: expression 3;
Int max = A> B? A: B;

Expression 1 is generally a relational expression.
If expression 1 is true, the value of expression 2 is the value of the entire ternary expression.
If the value of expression 1 is false, the value of expression 3 is the value of the entire ternary expression.
Note: The result type of expression 2 must be consistent with the result type of expression 3, and must be consistent with the result type of the entire ternary expression.

9. Random Number
Random r = new Random ();
Int number = r. Next (1, 11 );
Generate 1-10 numbers