Best way to change dictionary key

Question

I am wondering is there a better way to change a dictionary key, for example:

var dic = new Dictionary();
dic.Add(\"a\", 1);

Answer 1

public static bool ChangeKey(this IDictionary dict, 
                                           TKey oldKey, TKey newKey)
{
    TValue value;
    if (!dict.TryGetValue(oldKey, out value))
        return false;

    dict.Remove(oldKey);
    dict[newKey] = value;  // or dict.Add(newKey, value) depending on ur comfort
    return true;
}

Same as Colin's answer, but doesn't throw exception, instead returns false on failure. In fact I'm of the opinion that such a method should be default in dictionary class considering that editing the key value is dangerous, so the class itself should give us an option to be safe.

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Starting with .NET Core, this is more efficient:

public static bool ChangeKey(this IDictionary dict, 
                                           TKey oldKey, TKey newKey)
{
    TValue value;
    if (!dict.Remove(oldKey, out value))
        return false;

    dict[newKey] = value;  // or dict.Add(newKey, value) depending on ur comfort
    return true;
}