เมธอด Dictionary.Clear() ใน C# จะลบคู่คีย์/ค่าทั้งหมดออกจาก Dictionary
ไวยากรณ์
public void Clear();
ให้เราดูตัวอย่างการใช้เมธอด Dictionary.Clear() -
ตัวอย่าง
using System;
using System.Collections.Generic;
public class Demo {
public static void Main(){
Dictionary<string, string> dict =
new Dictionary<string, string>();
dict.Add("One", "John");
dict.Add("Two", "Tom");
dict.Add("Three", "Jacob");
dict.Add("Four", "Kevin");
dict.Add("Five", "Nathan");
Console.WriteLine("Count of elements = "+dict.Count);
Console.WriteLine("\nKey/value pairs...");
foreach(KeyValuePair<string, string> res in dict){
Console.WriteLine("Key = {0}, Value = {1}", res.Key, res.Value);
}
dict.Clear();
Console.WriteLine("Cleared Key/value pairs...");
foreach(KeyValuePair<string, string> res in dict){
Console.WriteLine("Key = {0}, Value = {1}", res.Key, res.Value);
}
Console.WriteLine("Count of elements now = "+dict.Count);
}
} ผลลัพธ์
สิ่งนี้จะสร้างผลลัพธ์ต่อไปนี้ -
Count of elements = 5 Key/value pairs... Key = One, Value = John Key = Two, Value = Tom Key = Three, Value = Jacob Key = Four, Value = Kevin Key = Five, Value = Nathan Cleared Key/value pairs... Count of elements now = 0
ให้เราดูตัวอย่างอื่นเพื่อนำเมธอด Dictionary.Clear() ไปใช้ −
ตัวอย่าง
using System;
using System.Collections.Generic;
public class Demo {
public static void Main(){
Dictionary<string, string> dict =
new Dictionary<string, string>();
dict.Add("One", "John");
dict.Add("Two", "Tom");
dict.Add("Three", "Jacob");
dict.Add("Four", "Kevin");
dict.Add("Five", "Nathan");
Console.WriteLine("Count of elements = "+dict.Count);
dict.Add("Six", "Anne");
dict.Add("Seven", "Katoe");
Console.WriteLine("Count of elements (updated) = "+dict.Count);
Console.WriteLine("Key/value pairs...");
foreach(KeyValuePair<string, string> res in dict){
Console.WriteLine("Key = {0}, Value = {1}", res.Key, res.Value);
}
dict.Clear();
Console.WriteLine("Cleared Key/value pairs...");
foreach(KeyValuePair<string, string> res in dict){
Console.WriteLine("Key = {0}, Value = {1}", res.Key, res.Value);
}
}
} ผลลัพธ์
สิ่งนี้จะสร้างผลลัพธ์ต่อไปนี้ -
Count of elements = 5 Count of elements (updated) = 7 Key/value pairs... Key = One, Value = John Key = Two, Value = Tom Key = Three, Value = Jacob Key = Four, Value = Kevin Key = Five, Value = Nathan Key = Six, Value = Anne Key = Seven, Value = Katoe Cleared Key/value pairs...
