Learning to use the system. Collections. sortedlist class of ASP. NET

Sortedlist is a "key/value" list class that can be automatically sorted (sort by key) and can access elements through indexes.

It is like upgrading hashtable (hash table). Every element of them is regarded as a dictionaryentry (key/value) structure.

Because it has more sorting and indexing than hashtable, it is less efficient than hashtable.

Main members:

 
/* Attribute */capacity; // capacity count; // number of elements keys; // icollection values; // icollection) /* Method */Add () // Add clear () // clear contains () // whether the specified key containskey () // same as contains () containsvalue () // include the specified value getbyindex () // obtain valuegetkey () based on the index // obtain the keygetkeylist () based on the index // obtain the Key List (ilist) getvaluelist () // Value List (ilist) indexofkey () // obtain the index indexofvalue () of the specified key // obtain the index of the specified value remove () // Delete removeat () according to the key value () // Delete setbyindex () based on the index // trimtosize () based on the index setting value // optimize the capacity (capacity = count)
 

The elements are automatically sorted:

 
Protected void button1_click (Object sender, eventargs e) {sortedlist slist = new sortedlist (); slist. add ("2 k", "x"); // The value can be repeated, and the key cannot be repeated slist. add ("1 K", "XX"); slist. add ("4 K", "XXX"); slist. add ("3 K", "XXXX"); string STR = ""; foreach (dictionaryentry de in slist) {STR + = string. format ("{0 }:{ 1} \ n", de. key, de. value);} textbox1.text = STR;}/******** 1 K: xx2k: x3k: xxxx4k: XXX *********/
 

Valid value:

Protected void button1_click (Object sender, eventargs e) {sortedlist slist = new sortedlist (); slist. add ("K1", "AAA"); slist. add ("K2", "BBB"); slist. add ("K3", "CCC"); slist. add ("K4", "DDD"); string S1 = slist ["K2"]. tostring (); // BBB string S2 = slist. getbyindex (1 ). tostring (); // BBB string S3 = slist. getkey (1 ). tostring (); // K2 textbox1.text = S1 + "\ n" + S2 + "\ n" + S3 ;}
 

Change Value:

 
Protected void button1_click (Object sender, eventargs e) {sortedlist slist = new sortedlist (); slist. add ("4", "AAA"); slist. add ("3", "BBB"); slist. add ("2", "CCC"); slist. add ("1", "DDD"); slist ["4"] = "AAA"; slist. setbyindex (1, "CCC"); string STR = ""; for (INT I = 0; I
 

Delete elements and retrieve indexes:

 
Protected void button1_click (Object sender, eventargs e) {sortedlist slist = new sortedlist (); slist. add ("4", "AAA"); slist. add ("3", "BBB"); slist. add ("2", "CCC"); slist. add ("1", "DDD"); If (slist. contains ("2") {slist. remove ("2");} // Delete 2/CCC if (slist. count> 0) {slist. removeat (slist. count-1);} // the index of the remaining elements will be deleted. 4/AAA // search for the index int n1 = slist. indexofkey ("3"); // 1 int n2 = slist. indexofkey ("1"); // 0 int N3 = slist. indexofvalue ("BBB"); // 1 int N4 = slist. indexofvalue ("DDD"); // 0 slist. clear (); int N5 = slist. indexofkey ("3"); //-1:-1 int N6 = slist. indexofvalue ("BBB"); //-1 textbox1.text = string. concat (N1 + "\ n" + N2 + "\ n" + N3 + "\ n" + N4 + "\ n" + N5 + "\ n" + N6 );}
 

Capacity, count, and trimtosize ():

Protected void button#click (Object sender, eventargs e) {sortedlist slist = new sortedlist (100); // reserved space for storing 100 elements int n1 = slist. capacity; // 100 int n2 = slist. count; // 0 slist. add (1,111); slist. add (2,222); int N3 = slist. capacity; // 100 int N4 = slist. count; // 2 slist. trimtosize (); int N5 = slist. capacity; // 2 int N6 = slist. count; // 2 textbox1.text = string. concat (N1 + "\ n" + N2 + "\ n" + N3 + "\ n" + N4 + "\ n" + N5 + "\ n" + N6 );}
 

Obtain the key set, value set, key list, and Value List respectively:

Protected void button1_click (Object sender, eventargs e) {sortedlist slist = new sortedlist (5); slist. add ("e", 5.55); slist. add ("C", 3.33); slist. add ("D", 4.44); slist. add ("A", 1.11); slist. add ("B", 2.22); icollection keys = slist. keys; icollection values = slist. values; ilist keylist = slist. getkeylist (); ilist ValueList = slist. getvaluelist (); string S1, S2, S3, S4; S1 = S2 = S3 = S4 = ""; foreach (var k in keys) {S1 + = K. tostring () + "";} // a B c d e foreach (VAR V in values) {S2 + = v. tostring () + "";} // 1.11 2.22 3.33 4.44 5.55 for (INT I = 0; I