Use char instead of string

Author: VahidN

src/iTextSharp.LGPLv2.Core/System/util/StringExtensions.cs

@@ -0,0 +1,79 @@
+#if NET40 || NETSTANDARD2_0
+namespace System;
+
+/// <summary>
+///     Missing NET4_6_2 exts
+/// </summary>
+internal static class StringExtensions
+{
+    /// <summary>
+    ///     Returns a new string in which all occurrences of a specified string in the current instance are replaced with
+    ///     another specified string, using the provided comparison type.
+    /// </summary>
+    public static bool Contains(this string commandText, string value, StringComparison comparisonType)
+        => !string.IsNullOrWhiteSpace(commandText) && commandText.IndexOf(value, comparisonType) >= 0;
+
+    /// <summary>
+    ///     Returns a new string in which all occurrences of a specified string in the current instance are replaced with
+    ///     another specified string, using the provided comparison type.
+    /// </summary>
+    public static string Replace(this string str, string oldValue, string newValue, StringComparison comparisonType)
+    {
+        newValue ??= string.Empty;
+
+        if (string.IsNullOrEmpty(str) || string.IsNullOrEmpty(oldValue) || oldValue.Equals(newValue, comparisonType))
+        {
+            return str;
+        }
+
+        int foundAt;
+
+        while ((foundAt = str.IndexOf(oldValue, startIndex: 0, comparisonType)) != -1)
+        {
+            str = str.Remove(foundAt, oldValue.Length).Insert(foundAt, newValue);
+        }
+
+        return str;
+    }
+
+    /// <summary>
+    ///     Returns the hash code for this string using the specified rules.
+    /// </summary>
+    public static int GetHashCode(this string str, StringComparison comparisonType)
+        => comparisonType switch
+        {
+            StringComparison.CurrentCulture => StringComparer.CurrentCulture.GetHashCode(str),
+            StringComparison.CurrentCultureIgnoreCase => StringComparer.CurrentCultureIgnoreCase.GetHashCode(str),
+            StringComparison.InvariantCulture => StringComparer.InvariantCulture.GetHashCode(str),
+            StringComparison.InvariantCultureIgnoreCase => StringComparer.InvariantCultureIgnoreCase.GetHashCode(str),
+            StringComparison.Ordinal => StringComparer.Ordinal.GetHashCode(str),
+            StringComparison.OrdinalIgnoreCase => StringComparer.OrdinalIgnoreCase.GetHashCode(str),
+            _ => throw new NotSupportedException()
+        };
+
+    /// <summary>
+    ///     Reports the zero-based index of the first occurrence of the specified string in the current String object. A
+    ///     parameter specifies the type of search to use for the specified string.
+    /// </summary>
+    public static int IndexOf(this string text, char value, StringComparison comparisonType)
+        => text.IndexOf(value.ToString(CultureInfo.InvariantCulture), comparisonType);
+
+    /// <summary>
+    ///     Determines whether the end of this string instance matches the specified string when compared using the specified
+    ///     comparison option.
+    /// </summary>
+    public static bool EndsWith(this string text,
+        char value,
+        StringComparison comparisonType = StringComparison.Ordinal)
+        => text.EndsWith(value.ToString(CultureInfo.InvariantCulture), comparisonType);
+
+    /// <summary>
+    ///     Determines whether the beginning of this string instance matches the specified string when compared using the
+    ///     specified comparison option.
+    /// </summary>
+    public static bool StartsWith(this string text,
+        char value,
+        StringComparison comparisonType = StringComparison.Ordinal)
+        => text.StartsWith(value.ToString(CultureInfo.InvariantCulture), comparisonType);
+}
+#endif

src/iTextSharp.LGPLv2.Core/iTextSharp/text/Anchor.cs

@@ -28,7 +28,7 @@ public class Anchor : Phrase
     /// <overloads>
     ///     Has nine overloads.
     /// </overloads>
-    public Anchor() : base(16)
+    public Anchor() : base(leading: 16)
     {
     }
 
@@ -104,6 +104,7 @@ public Anchor(float leading, string str, Font font) : base(leading, str, font)
     public Anchor(Phrase phrase) : base(phrase)
     {
         var anchor = phrase as Anchor;
+
         if (anchor != null)
         {
             var a = anchor;
@@ -124,8 +125,9 @@ public override IList<Chunk> Chunks
         get
         {
             var tmp = new List<Chunk>();
-            var localDestination = reference != null && reference.StartsWith("#", StringComparison.Ordinal);
+            var localDestination = reference != null && reference.StartsWith(value: '#');
             var notGotoOk = true;
+
             foreach (Chunk chunk in this)
             {
                 if (name != null && notGotoOk && !chunk.IsEmpty())
@@ -136,7 +138,7 @@ public override IList<Chunk> Chunks
 
                 if (localDestination)
                 {
-                    chunk.SetLocalGoto(reference.Substring(1));
+                    chunk.SetLocalGoto(reference.Substring(startIndex: 1));
                 }
                 else if (reference != null)
                 {
@@ -215,8 +217,9 @@ public override bool Process(IElementListener listener)
 
         try
         {
-            var localDestination = reference != null && reference.StartsWith("#", StringComparison.Ordinal);
+            var localDestination = reference != null && reference.StartsWith(value: '#');
             var notGotoOk = true;
+
             foreach (var chunk in Chunks)
             {
                 if (name != null && notGotoOk && !chunk.IsEmpty())
@@ -227,7 +230,7 @@ public override bool Process(IElementListener listener)
 
                 if (localDestination)
                 {
-                    chunk.SetLocalGoto(reference.Substring(1));
+                    chunk.SetLocalGoto(reference.Substring(startIndex: 1));
                 }
                 else if (reference != null)
                 {