當(dāng)前位置：首頁 > 编程语言 > asp.net >内容正文

asp.net

ASP.Net string 类的扩展方法 [转]

發(fā)布時間：2023/12/2 asp.net 30 豆豆

生活随笔收集整理的這篇文章主要介紹了 ASP.Net string 类的扩展方法 [转] 小編覺得挺不錯的,現(xiàn)在分享給大家,幫大家做個參考.

string 類的擴(kuò)展方法列表(基本相同于 IEnumerable<T> 接口的成員列表):

Aggregate<>? ? ?//累加 All<>? ? ? ? //是否都滿足條件 Any<>? ? ? ? //是否有一個滿足條件 AsEnumerable<>? // AsParallel<>? ? // AsQueryable<>? ? // Average<>? ? ? //平均值 Cast<>? ? ? // Concat<>? ? ? //連接 Contains<>? ? //是否包含 Count<>? ? ? //總數(shù) DefaultIfEmpty<>? //指定默認(rèn)空值 Distinct<>? ? //去除重復(fù) ElementAt<>? ? //獲取指定位置的元素 ElementAtOrDefault<> //同 ElementAt, 但獲取失敗則返回默認(rèn)的空值 Except<>? ? ? //差集 First<>? ? ? //獲取第一個元素 FirstOrDefault<>? //同 First, 但獲取失敗返回默認(rèn)的空值 GroupBy<>? ? ? //分組 GroupJoin<>? ? //關(guān)聯(lián)分組 Intersect<>? ? //交集 Join<>? ? ? //串聯(lián) Last<>? ? ? //獲取最后一個元素 LastOrDefault<>? //同 Last, 但獲取失敗返回默認(rèn)的空值 LongCount<>? ? //同 Count, 但返回 Int64 Max<>? ? ? ? //最大值 Min<>? ? ? ? //最小值 OfType<>? ? ? // OrderBy<>? ? ? //排序 OrderByDescending<> //倒排序 Reverse<>? ? ? //翻轉(zhuǎn) Select<>? ? ? //映射 SelectMany<>? ? //深度映射 SequenceEqual<>? // Single<>? ? ? //獲取只是唯一的元素, 不唯一或獲取不到則異常 SingleOrDefault<>? //獲取只是唯一的元素, 不唯一則異常, 獲取不到則取默認(rèn)空值 Skip<>? ? ? //獲取指定序號之后的 SkipWhile<>? ? //獲取指定條件之后的 Sum<>? ? ? ? //求和 Take<>? ? ? //獲取指定序號之前的 TakeWhile<>? ? //獲取指定條件之前的 ToArray<>? ? ? // ToCharArray<>? ? // ToDictionary<>? // ToList<>? ? ? // ToLookup<>? ? // Union<>? ? ? //并集 Where<>? ? ? //篩選 Zip<>? ? ? ? //合并

獲取首尾的字符(First、Last、FirstOrDefault、LastOrDefault):

/* 函數(shù)及重載 */ First <Char>()? ? ? ? ? ? ? // 函數(shù)名: First; <Char> 中的 Char 是返回值類型; () 表示這是一個無參數(shù)的重載 First <Char> (Func <Char, Boolean>)? ? // 這里的參數(shù)是個函數(shù), 其(函參)返回值是 Boolean 類型, 參數(shù)是 Char 類型. ? ? ? ? ? ? ? ? ? ? ? // <> 中是函數(shù)參數(shù)與返回值的列表, 最后一個是返回值. FirstOrDefault <Char>()? ? ? ? ? // 同 First, 但如果找不到則返回默認(rèn)值 null FirstOrDefault <Char> (Func <Char, Boolean>) // Last <Char>()? ? ? ? ? ? ? ? // 顧名思義, 同上 Last <Char> (Func <Char, Boolean>)? ? // LastOrDefault <Char>()? ? ? ? ? // LastOrDefault <Char> (Func <Char, Boolean>) // //下面例子很容易理解: protected void Button1_Click(object sender, EventArgs e) {string str = "ABCDEFG";char c1 = str.First(); // A ? char c2 = str.Last(); // G TextBox1.Text = string.Concat(c1, "\n", c2); }//下面例子使用了其第二種重載, 其參數(shù)是個函數(shù), 使用了 Lambda 匿名函數(shù)表達(dá)式: protected void Button2_Click(object sender, EventArgs e) {string str = "ABCDEFG";char c1 = str.First(p => p != 'A'); // B : 這是獲取不是 A 的第一個字符 ? char c2 = str.Last(p => p < 70);? // E : 這是獲取字符編碼值大于 70(F) 的倒數(shù)第一個字符 TextBox1.Text = string.Concat(c1, "\n", c2); }// Lambda 表達(dá)式中, // => 前面的是參數(shù)列表, 其類型可被自動識別所以可省略, 只有一個參數(shù)時可省略括號; 其中的 p 是自定義的變量名. // => 后面的是函數(shù)內(nèi)容, 通常只有一句話; 但其必須返回指定的類型(本例中是 Boolean). //測試用于其它數(shù)組: protected void Button3_Click(object sender, EventArgs e) {int[] nArr = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };string[] sArr = { "one", "two", "three", "four", "five", "six", "seven", "eight", "nine", "ten" };int n1 = nArr.First();? ? ? ? ? //1 ? int n2 = nArr.First(x => x % 2 == 0);? //2 ? string s1 = sArr.Last();? ? ? ? //ten ? string s2 = sArr.Last(s => s.Length == 5); //eight ? TextBox1.Text = string.Concat(n1, "\n", n2, "\n", s1, "\n", s2); }

獲取指定位置的元素(ElementAt、ElementAtOrDefault):

protected void Button1_Click(object sender, EventArgs e) {string str = "Asp.Net 4.0";char c1 = str.ElementAt(1);? ? ? //s ? char c2 = str.ElementAtOrDefault(1); //s ? char c3 = str.ElementAtOrDefault(999); // ? bool b1 = c3 == '\x00';? ? ? ? //True TextBox1.Text = string.Concat(c1, "\n", c2, "\n", c3, "\n", b1); }

統(tǒng)計操作(Aggregate、Count、LongCount、Max、Min、Sum、Average):

//用數(shù)字?jǐn)?shù)組測試比較合適 protected void Button1_Click(object sender, EventArgs e) {int[] nArr = { 2, 1, 4, 3, 6, 5 };int n1 = nArr.Count();? ? ? ? ? //6 ? int n2 = nArr.Count(n => n % 2 == 0);? //3 : 偶數(shù)元素總數(shù) ? int n3 = nArr.Sum();? ? ? ? ? //21 ? int n4 = nArr.Max();? ? ? ? ? //6 ? int n5 = nArr.Min();? ? ? ? ? //1 ? double n6 = nArr.Average();? ? ? //3.5 ? int n7 = nArr.Aggregate((x, y) => x * y); //720 : 累乘 ? Int64 n8 = nArr.LongCount();? ? ? //6 : LongCount 和 Count 只是返回值的類型不同 string r = "\n";TextBox1.Text = string.Concat(n1 + r + n2 + r + n3 + r + n4 + r + n5 + r + n6 + r + n7 + r + n8); }protected void Button2_Click(object sender, EventArgs e) {string str = "one two three four five six seven eight nine ten";int n1 = str.Count();? ? ? //48 : 這相當(dāng)于 str.Length ? int n2 = str.Count(s => s != ' '); //39 : 這是非空格字符的總數(shù) ? char c1 = str.Max();? ? ? //x : 這是序號最大的字符 ? char c2 = str.Min();? ? ? //序號最小的字符在這里是空格 TextBox1.Text = string.Concat(n1, "\n", n2, "\n", c1, "\n", c2); }//通過 Aggregate 翻轉(zhuǎn)字符串中的單詞 protected void Button3_Click(object sender, EventArgs e) {string str = "one two three four five six seven eight nine ten";string[] sArr = str.Split(' ');str = sArr.Aggregate((s1, s2) => s2 + " " + s1); //ten nine eight seven six five four three two one ? TextBox1.Text = str; }

集合操作(Intersect、Except、Union):

//測試整數(shù)數(shù)組的交集、差集、并集 protected void Button1_Click(object sender, EventArgs e) {int[] nArr1 = { 1, 2, 3, 4, 5, 6 };int[] nArr2 = { 4, 5, 6, 7, 8, 9 };IEnumerable<int> R1 = nArr1.Intersect(nArr2); // 返回類型可以寫作隱式類型 var ? var R2 = nArr1.Except(nArr2);var R3 = nArr1.Union(nArr2);string s1 = string.Join("", R1); //456 ? string s2 = string.Join("", R2); //123 ? string s3 = string.Join("", R3); //123456789 TextBox1.Text = string.Concat(s1, "\n", s2, "\n", s3); }//測試字符串(字符數(shù)組)的交集、差集、并集 protected void Button2_Click(object sender, EventArgs e) {string str1 = "Asp.Net 3.5";string str2 = "ASP.NET 4.0";var R1 = str1.Intersect(str2);var R2 = str1.Except(str2);IEnumerable<char> R3 = str1.Union(str2);string s1 = string.Join("", R1); //A.N ? string s2 = string.Join("", R2); //spet35 ? string s3 = string.Join("", R3); //Asp.Net 35SPET40 TextBox1.Text = string.Concat(s1, "\n", s2, "\n", s3); }//定義一個 Person 類, 其有 Name 和 Age 兩個屬性 public class Person {public string Name { get; set; }public int Age { get; set; }public Person(string name, int age) { Name = name; Age = age; } // 構(gòu)造函數(shù) }//自定義的對比類, 以比較是否是同一個人 public class PersonComparer : IEqualityComparer<Person> {public bool Equals(Person p1, Person p2){return p1.Name == p2.Name && p1.Age == p2.Age;}public int GetHashCode(Person obj){return 0;} }//獲取兩組人的交集、差集、并集 protected void Button3_Click(object sender, EventArgs e) {string s1, s2, s3;s1 = s2 = s3 = "";Person[] PersonArr1 = { new Person("AA", 11), new Person("BB", 22), new Person("CC", 33) };Person[] PersonArr2 = { new Person("CC", 33), new Person("DD", 44), new Person("AA", 55) };var ps1 = PersonArr1.Intersect(PersonArr2, new PersonComparer());var ps2 = PersonArr1.Except(PersonArr2, new PersonComparer());IEnumerable<Person> ps3 = PersonArr1.Union(PersonArr2, new PersonComparer());foreach (Person p in ps1) { s1 += string.Format("{0}:{1} ", p.Name, p.Age); } //CC:33 ? foreach (Person p in ps2) { s2 += string.Format("{0}:{1} ", p.Name, p.Age); } //AA:11 BB:22 ? foreach (Person p in ps3) { s3 += string.Format("{0}:{1} ", p.Name, p.Age); } //AA:11 BB:22 CC:33 DD:44 AA:55 TextBox1.Text = string.Concat(s1, "\n", s2, "\n", s3); }

連接、合并與串聯(lián)(Concat、Zip、Join):

//Concat protected void Button1_Click(object sender, EventArgs e) {int[] nArr1 = { 1, 2, 3 };int[] nArr2 = { 4, 5, 6 };var R1 = nArr1.Concat(nArr2);var R2 = nArr2.Concat(nArr1);var R3 = nArr1.Concat(nArr1);string s1 = string.Join("", R1); //123456 ? string s2 = string.Join("", R2); //456123 ? string s3 = string.Join("", R3); //123123 TextBox1.Text = string.Format("{0}\n{1}\n{2}", s1, s2, s3); }//Zip protected void Button2_Click(object sender, EventArgs e) {string[] sArr = { "one", "two", "there" };int[] nArr = { 1, 2, 3 };var R1 = sArr.Zip(nArr, (x1, x2) => x1 + ":" + x2 + " ");var R2 = sArr.Zip(nArr, (x1, x2) => x2 + ":" + x1 + " ");string s1 = string.Join("", R1); //one:1 two:2 there:3 ? string s2 = string.Join("", R2); //1:one 2:two 3:there TextBox1.Text = string.Concat(s1, "\n", s2); }//Join protected void Button3_Click(object sender, EventArgs e) {int[] nArr = { 1, 2, 3, 4, 5, 6, 7 };string[] sArr = { "one", "two", "three", "four", "five", "six", "seven", "eight", "nine", "ten" };var R = nArr.Join(sArr, n => n, s => s.Length, (n, s) => new { n, s });string str = "";foreach (var obj in R){str += obj.n + " : " + obj.s + "\n";}TextBox1.Text = str;/* 輸出結(jié)果:3 : one3 : two3 : six3 : ten4 : four4 : five4 : nine5 : three5 : seven5 : eight */ }

去除重復(fù)(Distinct):

protected void Button1_Click(object sender, EventArgs e) {string str = "aabbccc";var cs = str.Distinct();foreach (char c in cs) { TextBox1.Text += c; } //abc }protected void Button2_Click(object sender, EventArgs e) {int[] nArr = { 1, 3, 2, 4, 3, 5, 4, 6, 5, 7, 6, 8, 7, 9, 8, 0 };var ns = nArr.Distinct().OrderBy(x => -x);foreach (int n in ns) { TextBox1.Text += n.ToString(); } //9876543210 }

排序(OrderBy、OrderByDescending):

protected void Button1_Click(object sender, EventArgs e) {int[] nArr = { 1, 3, 2, 4, 3, 5 };string[] sArr = { "one", "two", "three", "four", "five", "six", "seven", "eight", "nine", "ten" };string str = "Asp.Net";var R1 = nArr.OrderBy(x => x);var R2 = nArr.OrderByDescending(x => x);var R3 = sArr.OrderBy(x => x);var R4 = sArr.OrderByDescending(x => x);var R5 = str.OrderBy(x => x.ToString().ToLower());var R6 = str.OrderByDescending(x => x.ToString().ToLower());string s1 = string.Join("", R1); //123345 ? string s2 = string.Join("", R2); //543321 ? string s3 = string.Join(" ", R3); //eight five four nine one seven six ten three two ? string s4 = string.Join(" ", R4); //two three ten six seven one nine four five eight ? string s5 = string.Join("", R5); //.AeNpst ? string s6 = string.Join("", R6); //tspNeA. TextBox1.Text = string.Concat(s1, "\n", s2, "\n", s3, "\n", s4, "\n", s5, "\n", s6); }

翻轉(zhuǎn)(Reverse):

protected void Button1_Click(object sender, EventArgs e) {string str = "Asp.Net";var cs = str.Reverse();foreach (char c in cs) { TextBox1.Text += c; } //teN.psA }

篩選(Where):

protected void Button1_Click(object sender, EventArgs e) {int[] nArr = { 1, 2, 3, 4, 5, 6, 7, 8, 9 };string[] sArr = { "one", "two", "three", "four", "five", "six", "seven", "eight", "nine", "ten" };var R1 = nArr.Where(n => n % 2 == 0);var R2 = sArr.Where(s => s.Length == 3);string s1 = string.Join(", ", R1); //2, 4, 6, 8 ? string s2 = string.Join(", ", R2); //one, two, six, ten TextBox1.Text = string.Concat(s1, "\n", s2); }

映射(Select、SelectMany):

//Select protected void Button1_Click(object sender, EventArgs e) {int[] nArr = { 1, 2, 3, 4, 5, 6, 7, 8, 9 };string[] sArr = { "one", "two", "three", "four", "five", "six", "seven", "eight", "nine", "ten" };var R1 = nArr.Select(n => n * n);var R2 = sArr.Select((str, index) => (index+1) + ":" + str.ToUpper());string s1 = string.Join(",", R1); //1,4,9,16,25,36,49,64,81 ? string s2 = string.Join(" ", R2); //1:ONE 2:TWO 3:THREE 4:FOUR 5:FIVE 6:SIX 7:SEVEN 8:EIGHT 9:NINE 10:TEN TextBox1.Text = string.Concat(s1, "\n", s2); }//Select 與 SelectMany protected void Button2_Click(object sender, EventArgs e) {string[] sArr = { "AA:BB:CC", "DD:EE:FF", "GG:HH:II" };var R1 = sArr.Select(arr => arr.Split(':'));var R2 = sArr.SelectMany(arr => arr.Split(':'));var s1 = string.Join(" ", R1); //System.String[] System.String[] System.String[] ? var s2 = string.Join(" ", R2); //AA BB CC DD EE FF GG HH II var s3 = "";foreach (string[] ss in R1) { s3 += string.Join(" ", ss) + "; "; } //AA BB CC; DD EE FF; GG HH II; TextBox1.Text = string.Concat(s1, "\n", s2 + "\n" + s3); }

分組(GroupBy、GroupJoin):

public class Person {public string Name { get; set; }public int Age { get; set; } } protected void Button1_Click(object sender, EventArgs e) {Person[] pArr = {new Person { Name="AA", Age=11 },new Person { Name="BB", Age=22 },new Person { Name="CC", Age=33 },new Person { Name="DD", Age=11 },new Person { Name="EE", Age=22 },new Person { Name="FF", Age=33 },new Person { Name="GG", Age=11 }};var R1 = pArr.GroupBy(p => p.Age, p => p.Name);var R2 = pArr.GroupBy(p => p.Age, p => p);string str1 = "";foreach (IGrouping<int, string> group in R1){str1 += group.Key + "\n";foreach (string n in group) { str1 += "\t" + n + "\n"; }}string str2 = "";foreach (IGrouping<int, Person> group in R2){str2 += group.Key + "\n";foreach (Person p in group){str2 += string.Format("\t{0}:{1}\n", p.Name, p.Age);}}TextBox1.Text = string.Format("{0}----------\n{1}", str1, str2);/* 輸出結(jié)果: 11AADDGG 22BBEE 33CCFF ---------- 11AA:11DD:11GG:11 22BB:22EE:22 33CC:33FF:33 */ }//使用 GroupJoin, 測試效果同上 protected void Button1_Click(object sender, EventArgs e) {int[] nArr = { 11, 22, 33 }; Person[] pArr = {new Person { Name="AA", Age=11 },new Person { Name="BB", Age=22 },new Person { Name="CC", Age=33 },new Person { Name="DD", Age=11 },new Person { Name="EE", Age=22 },new Person { Name="FF", Age=33 },new Person { Name="GG", Age=11 }};var R1 = nArr.GroupJoin(pArr, n => n, p => p.Age, (n, ps) => new { MyKey = n, MyNames = ps.Select(p => p.Name) });var R2 = nArr.GroupJoin(pArr, n => n, p => p.Age, (n, ps) => new { MyKey = n, MyNames = ps });string str1 = "";foreach (var obj in R1){str1 += obj.MyKey + "\n";foreach (string s in obj.MyNames){str1 += string.Format("\t{0}\n", s);}}string str2 = "";foreach (var obj in R2){str2 += obj.MyKey + "\n";foreach (var p in obj.MyNames){str2 += string.Format("\t{0}:{1}\n", p.Name, p.Age);}}TextBox1.Text = string.Format("{0}----------\n{1}", str1, str2); }

獲取指定條件之后的(Skip、SkipWhile)或之前的(Take、TakeWhile):

//Skip、SkipWhile protected void Button1_Click(object sender, EventArgs e) {int[] nArr = { 1, 3, 2, 4, 3, 5 };var R1 = nArr.Skip(3);? ? ? ? ? ? //取第 3 個元素之后的 ? var R2 = nArr.OrderBy(n => n).Skip(3);? ? //先排序, 再取第 3 個元素之后的 ? var R3 = nArr.OrderByDescending(n => n).Skip(3); //先倒排序, 再取第 3 個元素之后的 var R4 = nArr.OrderBy(n => n).SkipWhile(n => n <= 3); //先排序(123345), 從不滿足條件開始, 之后的 ? var R5 = nArr.SkipWhile((num, index) => num != index); // 從第二個元素開始, 數(shù)字和序號就不一樣了 string s1 = string.Join("", R1); //435 ? string s2 = string.Join("", R2); //345 ? string s3 = string.Join("", R3); //321 ? string s4 = string.Join("", R4); //45 ? string s5 = string.Join("", R5); //2435 TextBox1.Text = string.Format("{0}\n{1}\n{2}\n{3}\n{4}", s1, s2, s3, s4, s5); }//Take、TakeWhile 用法同上, 只是獲取之前的 protected void Button2_Click(object sender, EventArgs e) {int[] nArr = { 1, 3, 2, 4, 3, 5 };var R1 = nArr.Take(3);var R2 = nArr.OrderBy(n => n).Take(3);var R3 = nArr.OrderByDescending(n => n).Take(3);var R4 = nArr.OrderBy(n => n).TakeWhile(n => n <= 3);var R5 = nArr.TakeWhile((num, index) => num != index);string s1 = string.Join("", R1); //132 ? string s2 = string.Join("", R2); //123 ? string s3 = string.Join("", R3); //543 ? string s4 = string.Join("", R4); //1233 ? string s5 = string.Join("", R5); //13 TextBox1.Text = string.Format("{0}\n{1}\n{2}\n{3}\n{4}", s1, s2, s3, s4, s5); }

All 與 Any:

//都滿足條件時 All 才返回 True protected void Button1_Click(object sender, EventArgs e) {int[] nArr = { 1, 3, 5, 7, 9 };bool b1 = nArr.All(n => n % 2 == 0); //False ? bool b2 = nArr.All(n => n % 2 == 1); //True TextBox1.Text = string.Concat(b1, "\n", b2); }//其中一個滿足條件 Any 就返回 True protected void Button2_Click(object sender, EventArgs e) {string str1 = "Delphi";string str2 = "Asp.Net";string str3 = "";bool b1 = str1.Any();? ? ? //True ? bool b2 = str2.Any();? ? ? //True ? bool b3 = str3.Any();? ? ? //False bool b4 = str1.Any(c => c == 'D'); //True ? bool b5 = str2.Any(c => c == 'D'); //False ? bool b6 = str2.Any(c => c == 'D'); //False TextBox1.Text = string.Concat(b1, "\n", b2, "\n", b3, "\n", b4, "\n", b5, "\n", b6); }

是否包含(Contains):

protected void Button1_Click(object sender, EventArgs e) {string str = "Asp.Net 4.0";bool b1 = str.Contains('4');? //True ? bool b2 = str.Contains("Net 4.0"); //True ? bool b3 = str.Contains("Net4.0"); //False TextBox1.Text = string.Concat(b1, "\n", b2, "\n", b3, "\n"); }

獲取只是唯一的元素(Single、SingleOrDefault):

protected void Button1_Click(object sender, EventArgs e) {string str = "Microsoft";char c1, c2, c3, c4, c5, c6;c1 = c2 = c3 = c4 = c5 = c6 = '*';//Single ? c1 = str.Single(c => c == 'M'); //M try { c2 = str.Single(c => c == 'o'); }catch (Exception err) { Response.Write(err.Message + "<br/>"); } // 序列包含一個以上的匹配元素 try { c3 = str.Single(c => c == 'A'); }catch (Exception err) { Response.Write(err.Message + "<br/>"); } // 序列不包含任何匹配元素 //SingleOrDefault ? c4 = str.SingleOrDefault(c => c == 'M'); //M try { c5 = str.SingleOrDefault(c => c == 'o'); }catch (Exception err) { Response.Write(err.Message + "<br/>"); } // 序列包含一個以上的匹配元素 c6 = str.SingleOrDefault(c => c == 'A'); // 這不會激發(fā)異常 TextBox1.Text = string.Format("{0}{1}{2}{3}{4}{5}", c1, c2, c3, c4, c5, c6); //M**M* }

指定默認(rèn)空值(DefaultIfEmpty):

protected void Button1_Click(object sender, EventArgs e) {string str1 = "Asp.Net 3.5";string str2 = "";string r1 = string.Join("|", str1.DefaultIfEmpty());? //A|s|p|.|N|e|t| |3|.|5 ? string r2 = string.Join("|", str2.DefaultIfEmpty());? // ? string r3 = string.Join("|", str2.DefaultIfEmpty('*')); //* TextBox1.Text = string.Concat(r1, "\n", r2, "\n", r3); }

轉(zhuǎn)載于:https://www.cnblogs.com/lcxmvc/p/3292623.html

總結(jié)

以上是生活随笔為你收集整理的ASP.Net string 类的扩展方法 [转]的全部內(nèi)容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網(wǎng)站內(nèi)容還不錯，歡迎將生活随笔推薦給好友。

上一篇： Python模拟ICMP包
下一篇：群里分享的react的收藏一下！今日周末