Be( a)ware of String.Replace method

If you're using String.Replace method, you will encounter an ArgumentException if oldValue is null or empty.

This may be annoying if you don't check the old value or don't trap this exception.

A radical workaround would be to introduce a little overload with your own static method or by extending the System.String class with a "safe" method like :

/// <summary>
/// Extensions for System.String class
/// </summary>
public static class StringExtensions
{
    /// <summary>
    /// Safely replace all occurrences of specified System.String instance, with another System.String instance
    /// </summary>
    public static string SafeReplace(this string extendedString, string oldValue, string newValue)
    {
        if (string.IsNullOrEmpty(oldValue))
        {
            return extendedString;
        }

        return extendedString.Replace(oldValue, newValue);
    }
}

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