问使用string.replace()时的OutOfMemoryException

EN

string current = getChunk();
while (current.Length > 0)
{
    current = current.Replace(oldValue, newValue);
    string toSave = current.Substring(0, current.Length - oldValue.Length);
    saveToFile(toSave);
    current = current.Substring(current.Length - oldValue.Length) + getChunk();
}