[Collection] array tips

It was recorded that a lot of time was wasted for a small problem. Just like yesterday, it took nearly half an hour to tell a colleague that the lower limit is not a zero-dimensional array. Haha ~ Using system;
Using system. Collections. Generic;
Using system. text;

Namespace dotnetframework
{
Class Program
{
Static void main (string [] ARGs)
{
//-------------------------------------------------------------
// Create an array whose lower limit is not 0
// Defines the lower limit of the first and second dimensions of the array.
Int32 [] lowerbounds ={ 1995, 1 };
// Defines the length of the first and second parts of the array.
Int32 [] lengths = {12, 4 };
// Create an array
Decimal [,] Quarter = (decimal [,]) array. createinstance (typeof (decimal), lengths, lowerbounds );

// Access the Array
// Obtain the lower limit of the array
Int32 firstyear = quarter. getlowerbound (0 );
// Obtain the upper limit of the array
Int32 lastyear = quarter. getupperbound (0 );

For (int32 year = firstyear; year <= lastyear; year ++)
{
For (int32 quar = quarter. getlowerbound (1); quar <= quarter. getupperbound (1); quar ++)
{
Console. writeline (Year. tostring () + "" + quar. tostring ());
}
}
//-------------------------------------------------------------
// Some methods in. net2.0 are from msdn
Int32 [] arrtemp = {0, 1, 2, 3, 3, 3, 3, 7, 8, 9 };

// Determine whether the elements in the specified array match the conditions defined by the specified predicate.
Console. writeline (array. exists <int32> (arrtemp, validate ));
// The statement below is the same as above
Console. writeline (array. exists (arrtemp, validate ));

// Search for elements that match the conditions defined by the specified predicate and return the first matching item in the entire array.
Console. writeline (array. Find <int32> (arrtemp, validate ));
// The statement below is the same as above
Console. writeline (array. Find (arrtemp, validate ));

// Retrieve all elements that match the conditions defined by the specified predicate
Int32 [] arrsub = array. findall <int32> (arrtemp, validate );
// The statement below is the same as above
Int32 [] arrsub1 = array. findall (arrtemp, validate );
// And so on. See msdn
//-------------------------------------------------------------
// Re-adjust the array Length

Arrtemp = (int32 []) redim (arrtemp, 11 );

Arrtemp [10] = 100;

// Traverse the array and process each element of the array with action
Array. foreach <int32> (arrtemp, action );
// The statement below is the same as above
Array. foreach (arrtemp, action );

Console. Read ();
}

/// <Summary>
/// Re-adjust the array Length
/// </Summary>
/// <Param name = "oldarray"> target array </param>
/// <Param name = "newsize"> New length </param>
/// <Returns> A new array with a new length </returns>
/// <Remarks> Of course, it is necessary to perform a verification :) description </remarks>
Static array redim (array oldarray, int32 newsize)
{
// Obtain the array element type
Type T = oldarray. GetType (). getelementtype ();
// Create an array with a new length and its type matches the original array
Array newarray = array. createinstance (T, newsize );
// Copy data
Array. Copy (oldarray, 0, newarray, 0, math. Min (oldarray. length, newsize ));
Return newarray;
}

/// <Summary>
/// Generic delegation Method
/// </Summary>
/// <Param name = "I"> </param>
Static void action (int32 I)
{
Console. writeline (I );
}

/// <Summary>
/// Generic delegation Method
/// </Summary>
/// <Param name = "I"> </param>
/// <Returns> </returns>
Static bool validate (int32 I)
{
If (int32.equals (3, I ))
{
Return true;
}

Return false;
}
}
}