Looking for a slicker way to convert delimited string to StringDictionary
I have created the following to expose some data as a regex match string as well as a StringDictionary. It feels like I could do this using LINQ with fewer lines.
private const string STREETTYPES = @"ALY|Alley|AVE|Avenue|BLVD|Boulevard|CIR|Circle|CT|Court|CTR|Center|DR|Drive|EXPY|Expressway|FWY|Freeway|HALL|Hall|HWY|Highway|JCT|Junction|LN|Lane|LP|Loop|PIKE|Pike|PKWY|Parkway|PL|Place|RD|Road|ST|Street|TER|Terrace|TPKE|Turnpike|TRL|Trail|WAY|Way";
private static StringDictionary streetTypes = null;
public static StringDictionary StreetTypes
{
get
{
if (streetTypes != null) return streetTypes;
streetTypes = new StringDictionary();
va开发者_开发问答r streetArray = STREETTYPES.Split(PIPE);
for (int i = 0; i < streetArray.Length-1; i = i+2)
{
streetTypes.Add(streetArray[i], streetArray[i + 1]);
}
return streetTypes;
}
}
How about just:
private static readonly StringDictionary streetTypes = new StringDictionary
{
{"ALY","Alley"},{"AVE","Avenue"},{"ALY","Alley"},{"BLVD","Boulevard"},{"CIR","Circle"},
{"CT","Court"},{"CTR","Center"},{"DR","Drive"},{"EXPY","Expressway"},{"FWY","Freeway"},
{"HALL","Hall"},{"HWY","Highway"},{"JCT","Junction"},{"LN","Lane"},{"LP","Loop"},
...
};
You could use Linq if you need to recompute - but if the dictionary is static just use the initializer:
var input = STREETTYPES.Split('|');
var dict = input.Select( (x,i) => new { Item = x, Index = i })
.Where(x => x.Index % 2 == 0)
.ToDictionary( x=> input[x.Index], x => input[x.Index + 1]);
This any good?
var x = STREETTYPES.Split(new[] {'|'});
var output = Enumerable
.Range(0, x.Length / 2)
.ToDictionary(s => x[2 * s], s => x[2 * s + 1]);
Might be possible to compact it further but I'm half asleep tonight.
This will give you the StringDictionary
you seek without doing positional math. If you can use a Dictionary
, I'd go with it and one of the other posted solutions.
var types = new StringDictionary();
using (IEnumerator<string> enumerator = streetTypes.Split('|').AsEnumerable().GetEnumerator())
{
while(enumerator.MoveNext())
{
string first = enumerator.Current;
if (!enumerator.MoveNext())
break;
types.Add(first, enumerator.Current);
}
}
Shamelessly ripping off a Python dict constructor:
IDictionary<TKey, TVal>
ToDictionary<TKey, TVal>(IEnumerable<TKey> keys,
IEnumerable<TVal> values)
{
return keys.Zip(values, (k, v)=>new {K=k, V=v}).ToDictionary(kv=>kv.K, kv=>kv.V);
}
var str = @"ALY|Alley|AVE|Avenue|BLVD|Boulevard|CIR|Circle|CT|Court|CTR|Center|DR|Drive|EXPY|Expressway|FWY|Freeway|HALL|Hall|HWY|Highway|JCT|Junction|LN|Lane|LP|Loop|PIKE|Pike|PKWY|Parkway|PL|Place|RD|Road|ST|Street|TER|Terrace|TPKE|Turnpike|TRL|Trail|WAY|Way";
var words = str.Split('|');
var keys = words.Where((w, i) => i%2 == 0);
var values = words.Where((w, i) => i%2 != 0);
var dict = ToDictionary(keys, values);
This will produce a Dictionary<string, string>
, not a StringDictionary
. The latter doesn't have any copy constructors, so it can't be created with a oneliner.
(Now I'm wishing C# had less rudimentary support for ad-hoc data structures, I miss destructuring assignments.)
Alternative version that doesn't require Zip() and will thus work on older versions of .NET, and avoids allocating a list of temporary key/value pairs:
IDictionary<TKey, TVal>
ToDictionary<TKey, TVal>(IEnumerable<TKey> keys,
IEnumerable<TVal> values)
{
return Enumerable.Range(0, keys.Count()).ToDictionary(i=>keys.ElementAt(i), i=>values.ElementAt(i));
}
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