Array, collection, string manipulation, function summary

The array is stored in contiguous data of the same type.

One-dimensional arrays:

Definition: Data type [] Array name = new data type [array length];

data type [] Array name = new data type [array length]{element 1, Element 2, Element 3 ...};

For example: 1, int[] A = new int[5];

2, int[] a = new int[]{1,2,3,4,5}

Question: The array length in Example 2 can not be written, please answer in the comments

Description

1. Data type [] indicates array type

Array names represent array variables

New represents the creation

data type [array length] array length cannot be empty (first definition)

2, array subscript: Used to determine the position of each element in the array, array subscript starting from 0

3, Array Assignment: array name [array subscript] = value Note data type is the same

4. Array values: variable = array name [array subscript] Note data types are the same

5, the array traversal:

　　　　　　For loop traversal array　　　　　　　

Int[] A = new int[5];

for (int i = 0;i<a.length;i++) //a.length represents the length of the array

{ //need to be aware of the relationship between array length and subscript

Console.WriteLine (A[i]);

}

　　　　　　foreach Traversal array　　　　　　　

Int[] A = new int[5];

foreach (int i in a)

{

Console.WriteLine (i);

}

How to see the blog: Array manipulation

Two-dimensional arrays

Definition: Data type [,] array name = new data type [number of rows, number of columns];

data type [,] array name = new data type [3,2]{{1,2},{2,3},{3,4}};

For example: int[,] a = new int[3,4];

......

Description: 1, noun interpretation of the same dimension array

2, array subscript the same dimension array

3, Array Assignment: data type [row subscript, column subscript] = value

a[0,0] = 1;

4, Array value: Data type [row subscript, column subscript]

5, the array traversal:

　　　　　　　For loop traversal array　　　　　　　

int[,] a = new int[3,4];

for (int i = 0;i<3;i++)

{

for (int j = 0;i<4;j++)

{

Console.WriteLine (A[i,j]);

}

}

How to read the blog: two-dimensional array manipulation

Jagged arrays: Arrays of arrays

Definition: First step: defining large arrays

Data type [] a= new data type [number of rows] []; number of columns not written

Step two: Define the decimal group

Data type [] a1 = new data type [number of columns];

Data type [] a2 = new data type [number of columns];

......

Step three: Put the decimal group in a large array

A[0] = A1;

A[1] = A2;

......

Comparison of two-dimensional arrays with jagged arrays:

　　　　　　

　　

Array, collection, string manipulation, function summary