Is it possible to do a partial string match on a Dictionary string key in C#?

Is it possible to do a partial string match on a Dictionary string key in C#?

In C#, the Dictionary<TKey, TValue> class does not provide direct support for partial string matching on keys. By default, dictionary lookups are performed using exact matching on the key.

However, you can achieve partial string matching on keys by implementing custom logic. Here's an example:

using System;
using System.Collections.Generic;

public class Program
{
    public static void Main()
    {
        Dictionary<string, string> dictionary = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);

        // Add items to the dictionary
        dictionary.Add("apple", "A fruit");
        dictionary.Add("banana", "A fruit");
        dictionary.Add("orange", "A fruit");
        dictionary.Add("cat", "An animal");
        dictionary.Add("dog", "An animal");
        dictionary.Add("elephant", "An animal");

        string partialKey = "ap";

        foreach (KeyValuePair<string, string> pair in dictionary)
        {
            if (pair.Key.StartsWith(partialKey, StringComparison.OrdinalIgnoreCase))
            {
                Console.WriteLine($"Key: {pair.Key}, Value: {pair.Value}");
            }
        }
    }
}

In this example, we create a Dictionary<string, string> named dictionary with case-insensitive key comparison (StringComparer.OrdinalIgnoreCase). We add some items to the dictionary with keys and corresponding values.

To perform a partial string match, we define a partialKey string variable with the desired partial key value. We then iterate over the key-value pairs of the dictionary and use the StartsWith method to check if the key starts with the partialKey string. We can use the StringComparison.OrdinalIgnoreCase option to perform a case-insensitive match.

If the key starts with the partialKey, we can perform the desired operations with the key-value pair. In this example, we print the matching key-value pairs to the console.

By implementing custom logic using methods like StartsWith, Contains, or regular expressions, you can achieve partial string matching on dictionary keys based on your specific requirements.

Examples

  1. Partial string match in Dictionary key C#

    • Description: Learn how to perform a partial string match on Dictionary keys using LINQ.
    // Example using LINQ for partial string match on Dictionary keys
var partialKey = "partial";
var matchingPairs = myDictionary.Where(pair => pair.Key.Contains(partialKey))
                                .ToDictionary(pair => pair.Key, pair => pair.Value);

  2. Case-insensitive partial string match in Dictionary key C#

    • Description: Explore case-insensitive partial string matching on Dictionary keys.
    // Example using case-insensitive partial string match on Dictionary keys
var partialKey = "Partial";
var matchingPairs = myDictionary.Where(pair => pair.Key.IndexOf(partialKey, StringComparison.OrdinalIgnoreCase) >= 0)
                                .ToDictionary(pair => pair.Key, pair => pair.Value);

  3. Partial string match using Regex in Dictionary key C#

    • Description: Understand how to use regular expressions for partial string matching on Dictionary keys.
    // Example using Regex for partial string match on Dictionary keys
var partialKey = "partial";
var matchingPairs = myDictionary.Where(pair => Regex.IsMatch(pair.Key, $".*{partialKey}.*"))
                                .ToDictionary(pair => pair.Key, pair => pair.Value);

  4. Dictionary key starts with a partial string match in C#

    • Description: Learn how to filter Dictionary keys that start with a specific partial string.
    // Example filtering Dictionary keys starting with a partial string match
var partialKey = "partial";
var matchingPairs = myDictionary.Where(pair => pair.Key.StartsWith(partialKey))
                                .ToDictionary(pair => pair.Key, pair => pair.Value);

  5. Dictionary key ends with a partial string match in C#

    • Description: Explore filtering Dictionary keys that end with a specific partial string.
    // Example filtering Dictionary keys ending with a partial string match
var partialKey = "partial";
var matchingPairs = myDictionary.Where(pair => pair.Key.EndsWith(partialKey))
                                .ToDictionary(pair => pair.Key, pair => pair.Value);

  6. Partial string match using StringComparison in Dictionary key C#

    • Description: Understand how to use StringComparison for a more controlled partial string match on Dictionary keys.
    // Example using StringComparison for partial string match on Dictionary keys
var partialKey = "partial";
var matchingPairs = myDictionary.Where(pair => pair.Key.IndexOf(partialKey, StringComparison.CurrentCultureIgnoreCase) >= 0)
                                .ToDictionary(pair => pair.Key, pair => pair.Value);

  7. Dictionary key contains a partial string match with custom comparison in C#

    • Description: Explore a custom comparison method for a partial string match on Dictionary keys.
    // Example using a custom comparison for partial string match on Dictionary keys
var partialKey = "partial";
var matchingPairs = myDictionary.Where(pair => ContainsPartial(pair.Key, partialKey, StringComparison.OrdinalIgnoreCase))
                                .ToDictionary(pair => pair.Key, pair => pair.Value);

// Custom comparison method
bool ContainsPartial(string source, string partial, StringComparison comparison)
{
    return source.IndexOf(partial, comparison) >= 0;
}

  8. Partial string match with wildcard characters in Dictionary key C#

    • Description: Understand how to use wildcard characters for a flexible partial string match on Dictionary keys.
    // Example using wildcard characters for partial string match on Dictionary keys
var partialKey = "*part*";
var regexPattern = "^" + Regex.Escape(partialKey).Replace("\\*", ".*") + "$";
var matchingPairs = myDictionary.Where(pair => Regex.IsMatch(pair.Key, regexPattern))
                                .ToDictionary(pair => pair.Key, pair => pair.Value);

  9. Partial string match using Levenshtein distance in Dictionary key C#

    • Description: Explore using Levenshtein distance for approximate partial string matching on Dictionary keys.
    // Example using Levenshtein distance for approximate partial string match on Dictionary keys
var partialKey = "partial";
var matchingPairs = myDictionary.Where(pair => LevenshteinDistance(pair.Key, partialKey) <= 2)
                                .ToDictionary(pair => pair.Key, pair => pair.Value);

// Levenshtein distance calculation
int LevenshteinDistance(string s, string t)
{
    // Implementation of Levenshtein distance algorithm
    // ...
}

  10. Partial string match using Fuzzy Matching algorithm in Dictionary key C#

    • Description: Learn how to use a Fuzzy Matching algorithm for approximate partial string matching on Dictionary keys.
    // Example using a Fuzzy Matching algorithm for approximate partial string match on Dictionary keys
var partialKey = "partial";
var matchingPairs = myDictionary.Where(pair => FuzzyMatch(pair.Key, partialKey))
                                .ToDictionary(pair => pair.Key, pair => pair.Value);

// Fuzzy Matching algorithm
bool FuzzyMatch(string source, string target)
{
    // Implementation of Fuzzy Matching algorithm
    // ...
}

More Tags

file-handling database-dump dotnet-cli bokeh euclidean-distance for-loop large-title innerhtml postman-collection-runner dollar-quoting

More C# Questions

More Electronics Circuits Calculators

More Fitness Calculators

More Mortgage and Real Estate Calculators

More Chemical thermodynamics Calculators