Adding c# snippets

Author: chaitanya-jvnm

snippets/csharp/basics/hello-world.md

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+---
+title: Hello, World!
+description: Prints Hello, World! to the terminal.
+author: chaitanya-jvnm
+tags: c#,printing,hello-world,utility
+---
+
+```c#
+public class Program {
+  public static void Main(string[] args) {
+    System.Console.WriteLine("Hello, World!");
+  }
+}
+```

snippets/csharp/guid-utilities/generate-guid.md

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+---
+title: Hello, World!
+description: Generates a new GUID
+author: chaitanya-jvnm
+tags: c#,guid,generate,utility
+---
+
+```c#
+public static string GenerateGuid() {
+  return Guid.NewGuid().ToString();
+}
+```

snippets/csharp/guid-utilities/guid-to-byte-array.md

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+---
+title: Hello, World!
+description: Converts a GUID to a byte array.
+author: chaitanya-jvnm
+tags: c#,guid,byte-array,utility
+---
+
+```c#
+public static byte[] GuidToByteArray(string guid) {
+  return new Guid(guid).ToByteArray();
+}
+```

snippets/csharp/guid-utilities/validate-guid.md

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+---
+title: Hello, World!
+description: Checks if a string is a valid GUID.
+author: chaitanya-jvnm
+tags: c#,guid,validate,utility
+---
+
+```c#
+public static bool IsGuid(string str) {
+  return Guid.TryParse(str, out _);
+}
+```

snippets/csharp/jwt-utilities/decode-jwt.md

@@ -0,0 +1,12 @@
+---
+title: Hello, World!
+description: Decodes a JWT.
+author: chaitanya-jvnm
+tags: c#,jwt,decode,utility
+---
+
+```c#
+public static string DecodeJwt(string token) {
+  return new JwtSecurityTokenHandler().ReadJwtToken(token).ToString();
+}
+```

snippets/csharp/jwt-utilities/generate-jwt.md

@@ -0,0 +1,15 @@
+---
+title: Hello, World!
+description: Generates a new JWT.
+author: chaitanya-jvnm
+tags: c#,jwt,generate,utility
+---
+
+```c#
+public static string GenerateJwt(string secret, string issuer, string audience, int expirationMinutes) {
+  var securityKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(secret));
+  var credentials = new SigningCredentials(securityKey, SecurityAlgorithms.HmacSha256);
+  var token = new JwtSecurityToken(issuer, audience, null, expires: DateTime.UtcNow.AddMinutes(expirationMinutes), signingCredentials: credentials);
+  return new JwtSecurityTokenHandler().WriteToken(token);
+}
+```

snippets/csharp/jwt-utilities/validate-jwt.md

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+---
+title: Hello, World!
+description: Validates a JWT.
+author: chaitanya-jvnm
+tags: c#,jwt,validate,utility
+---
+
+```c#
+public static bool ValidateJwt(string token, string secret) {
+  var tokenHandler = new JwtSecurityTokenHandler();
+  var validationParameters = new TokenValidationParameters {
+    ValidateIssuerSigningKey = true,
+    IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(secret)),
+    ValidateIssuer = false,
+    ValidateAudience = false
+  };
+  try {
+    tokenHandler.ValidateToken(token, validationParameters, out _);
+    return true;
+  }
+  catch {
+    return false
+  }
+}
+```

snippets/csharp/string-utilities/capitalize-first-letter.md

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+---
+title: Hello, World!
+description: Makes the first letter of a string uppercase.
+author: chaitanya-jvnm
+tags: c#,string,capitalize,utility
+---
+
+```c#
+/// <summary>
+/// Capitalize the first character of the string
+/// <summary>
+public static string Capitalize(this string str) {
+  return str.Substring(0, 1).ToUpper() + str.Substring(1);
+}
+```

snippets/csharp/string-utilities/split-string.md

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+---
+title: Hello, World!
+description: Splits a string by a delimiter.
+author: chaitanya-jvnm
+tags: c#,string,split,utility
+---
+
+```c#
+public static string[] SplitString(string str, string delimiter) {
+  return str.Split(delimiter);
+}
+```