I want populate a TokenBox from a database using the property tokenBoxSettings.Properties.DataSource
TokenBoxView.cshtml
groupSettings.Items.Add(
formLayoutSettings.Items.Add(i =>
{
i.FieldName = "email";
i.Caption = "Email";
i.NestedExtensionType = FormLayoutNestedExtensionItemType.TokenBox;
TokenBoxSettings tokenBoxSettings = (TokenBoxSettings) i.NestedExtensionSettings;
tokenBoxSettings.Width = 350;
//data binding
tokenBoxSettings.Properties.DataSource = mainController.GetMails();
tokenBoxSettings.Properties.TextField = "email_empresarial";
tokenBoxSettings.Properties.ValueField = "email_empresarial";
tokenBoxSettings.Properties.IncrementalFilteringMode = IncrementalFilteringMode.Contains;
tokenBoxSettings.Properties.ValueSeparator = ';';
})
);
TokenBoxController.cs
//mainController
//I created a dictionary based on the result of select
public Dictionary<string, string> GetMails()
{
var email = db.usuario.ToList().Select(e => new { e.email_empresarial });
var emails = new Dictionary<string, string>();
foreach (var mail in email)
{
correos.Add(mail.ToString(), mail.ToString());
}
return emails;
}
But it shows me the "object explicitly", I only need the value, for example kenneth or manuel
tokenBox list
What am I doing wrong? or with what other approach I can do?
You are specifying same email_empresarial field name for both tokenBoxSettings.Properties.TextField and tokenBoxSettings.Properties.ValueField.
Since you are binding your TokenBox to Dictionary, try changing settings for TextField and ValueField to reference Dictionary Key and Value, like this:
tokenBoxSettings.Properties.TextField = "Value";
tokenBoxSettings.Properties.ValueField = "Key";
Also, in your GetMail() method you have declared the var emails but in the loop you are adding items to the undeclared correos variable. Are you sure you don't have a bug here?
Another note, in the Dictionary returned by GetMails() you populate both dictionary keys and values with the same value of mail.ToString(). Are you sure you really need to use Dictionary to bind your TokenBox? If keys and values are equal you may try going with plain List<string>.
I am writing unit tests for my asp.net web API application and one of them is trying to verify that AddOrGetExisting is working correctly. According to the MSDN documentation, AddOrGetExisting returns an item if it's already saved, and if not it should write it into Cache.
The problem I am having is that if I add the key to MemoryCache object from an unit test, then call AddOrGetExisting, it will always return null and overwrite the value instead of returning the value that is already saved. I am verifying that the value is in the cache right before I call AddOrGetExisting(bool isIn evaluates to true).
Here is the code for my memory cache and the test method. Any help would be much appreciated:
public static class RequestCache
{
public static TEntity GetFromCache<TEntity>(string key, Func<TEntity> valueFactory) where TEntity : class
{
ObjectCache cache = MemoryCache.Default;
var newValue = new Lazy<TEntity>(valueFactory);
CacheItemPolicy policy = new CacheItemPolicy { AbsoluteExpiration = DateTimeOffset.Now.AddMinutes(60) };
bool isIn = cache.Contains(key);
// Returns existing item or adds the new value if it doesn't exist
var value = cache.AddOrGetExisting(key, newValue, policy) as Lazy<TEntity>;
return (value ?? newValue).Value;
}
}
public string TestGetFromCache_Helper()
{
return "Test3and4Values";
}
[TestMethod]
public void TestGetFromCache_ShouldGetItem()
{
ObjectCache cache = MemoryCache.Default;
CacheItemPolicy policy = new CacheItemPolicy { AbsoluteExpiration = DateTimeOffset.Now.AddMinutes(60) };
var cacheKey = "Test3";
var expectedValue = "Test3Value";
cache.AddOrGetExisting(cacheKey, expectedValue, policy);
var result = Models.RequestCache.GetFromCache(cacheKey,
() =>
{
return TestGetFromCache_Helper();
});
Assert.AreEqual(expectedValue, result);
}
The issue may be that you're passing a Lazy<TEntity> as newValue within RequestCache.GetFromCache but passing a string as expectedValue in the test method.
When running the test, the cache.Contains(key) confirms that there is a value stored for that key, which is true. However it is a string instead of a Lazy<TEntity>. Apparently AddOrGetExisting decides to overwrite the value in that case.
The fix for this particular scenario may be to adjust the expectedValue assignment in your test to something like this:
var expectedValue = new Lazy<string>(TestGetFromCache_Helper);
You'd also need to pull the value from the Lazy in the test's final equality comparison, for example:
Assert.AreEqual(expectedValue.Value, result);
I have a enum that's contain Description Attribute(for audit):
public enum ActivityType
{
[NotExist("Not Assign")]
[Description("Change Level")]
LevelChanged,
[NotExist("Not Assign")]
[Description("Change Skill Level")]
SkillLevelChanged
}
And all had been great until i needed to put Desription in Resource files(attribute didn't support them), so i need Dictionary or something like this.The question is: How implement this feature without big changing in all another logic?Something like this:
private static readonly Dictionary<ActivityType, String> ActivityDescription = new Dictionary<ActivityType, String>()
{
{ActivityType.LevelChanged, "Change"},
{ActivityType.SkillLevelChanged, "SkillChange"}
}
The solution that requires the minimal amount of code change for you would be to alter your descriptions to be the resource keys in your resource file. Then you could read these dynamically by doing something like:
[Description("Change_Level")]
Then your resource key/value would be:
Change_Level Change Level
And to read it you can do:
FieldInfo fi = value.GetType().GetField(value.ToString());
DescriptionAttribute attribute = value.GetType()
.GetField(value.ToString())
.GetCustomAttributes(typeof(DescriptionAttribute), false)
.SingleOrDefault() as DescriptionAttribute;
if (attribute != null)
{
var resManager = new ResourceManager(typeof(MyResources));
return resManager.GetString(attribute.Description);
}
else
{
return value.ToString();
}
If however you're wanting a nicer solution with the option to pass in the resource file, you can hijack the Display attribute:
[Display(ResourceType = typeof(MyResources), Name = "Change_Level")]
Then you can do:
FieldInfo fi = value.GetType().GetField(value.ToString());
DisplayAttribute attribute = value.GetType()
.GetField(value.ToString())
.GetCustomAttributes(typeof(DisplayAttribute), false)
.SingleOrDefault() as DisplayAttribute;
if (attribute != null)
{
var resManager = new ResourceManager(attribute.ResourceType);
return resManager.GetString(attribute.Name);
}
else
{
return value.ToString();
}
asp.net C#4
I have a simple class to working with query strings.
A new instance is created like this:
public QueryString(string querystring)
{
try
{
_table = new Hashtable();
if (querystring.Length > 0)
{
foreach (string pair in querystring.Split('&'))
{
string[] item = pair.Split('=');
_table.Add(item[0].ToLower(), item[1]);
}
}
}
catch (Exception)
{
}
}
I want to add a method to this that will remove a key value pair. I don't want it to return a new querystring, I just want it to remove the pair from the current instance. Not sure how to do that since it says I can't assign a value to 'this'
public void Remove(string key)
{
String querystring = this.ToString();
try
{
_table = new Hashtable();
if (key.Length > 0)
{
foreach (string pair in querystring.Split('&'))
{
string[] item = pair.Split('=');
if (item[0] != key)
{
_table.Add(item[0].ToLower(), item[1]);
}
}
this = _table;
}
}
catch (Exception)
{
}
}
You're overcomplicating things. Since your class's state is made up of the _table field, all you need to do is remove the item with the given key from that field.
The following example replaces your untyped Hashtable wit a strongly-typed Dictionary. I also chose to initialize the dictionary with a LINQ statement, but you could keep your old code there if you prefer.
public class QueryString
{
private readonly Dictionary<string, string> _table;
public QueryString(string querystring)
{
if (querystring.Length > 0)
{
var pairs =
from pair in querystring.Split('&')
let item = pair.Split('=')
select new {key = item[0], value = item[1]};
_table = pairs.ToDictionary(p => p.key, p => p.value);
}
}
public void Remove(string key)
{
_table.Remove(key);
}
}
You cannot assign a value to this since it is a reference to the object itself.
However, if you remove the line this = _table; , isn't things working as they should then? I guess your ToString() is somewhat using the hashtable to generate a "printer friendly" QueryString, and if that is the case, the way I see it, your Remove() method should be working (since you are replacing the _table variable with a new HashTable not including the key-value pair you want to exclude).
you are passing a querystring into the class so the original querystring IS intact.
However you then break down the querystring into a a Hashtable of key/value pairs. If you want to keep THAT intact you need to clone the HashTable and perform the remove on the clone.
In any case it's probably a good idea to keep the querystring you are passing in as a constructor parameter in a member variable for safe keeping.
I know i can do this
var nv = HttpUtility.ParseQueryString(req.RawUrl);
But is there a way to convert this back to a url?
var newUrl = HttpUtility.Something("/page", nv);
Simply calling ToString() on the NameValueCollection will return the name value pairs in a name1=value1&name2=value2 querystring ready format. Note that NameValueCollection types don't actually support this and it's misleading to suggest this, but the behavior works here due to the internal type that's actually returned, as explained below.
Thanks to #mjwills for pointing out that the HttpUtility.ParseQueryString method actually returns an internal HttpValueCollection object rather than a regular NameValueCollection (despite the documentation specifying NameValueCollection). The HttpValueCollection automatically encodes the querystring when using ToString(), so there's no need to write a routine that loops through the collection and uses the UrlEncode method. The desired result is already returned.
With the result in hand, you can then append it to the URL and redirect:
var nameValues = HttpUtility.ParseQueryString(Request.QueryString.ToString());
string url = Request.Url.AbsolutePath + "?" + nameValues.ToString();
Response.Redirect(url);
Currently the only way to use a HttpValueCollection is by using the ParseQueryString method shown above (other than reflection, of course). It looks like this won't change since the Connect issue requesting this class be made public has been closed with a status of "won't fix."
As an aside, you can call the Add, Set, and Remove methods on nameValues to modify any of the querystring items before appending it. If you're interested in that see my response to another question.
string q = String.Join("&",
nvc.AllKeys.Select(a => a + "=" + HttpUtility.UrlEncode(nvc[a])));
Make an extension method that uses a couple of loops. I prefer this solution because it's readable (no linq), doesn't require System.Web.HttpUtility, and it supports duplicate keys.
public static string ToQueryString(this NameValueCollection nvc)
{
if (nvc == null) return string.Empty;
StringBuilder sb = new StringBuilder();
foreach (string key in nvc.Keys)
{
if (string.IsNullOrWhiteSpace(key)) continue;
string[] values = nvc.GetValues(key);
if (values == null) continue;
foreach (string value in values)
{
sb.Append(sb.Length == 0 ? "?" : "&");
sb.AppendFormat("{0}={1}", Uri.EscapeDataString(key), Uri.EscapeDataString(value));
}
}
return sb.ToString();
}
Example
var queryParams = new NameValueCollection()
{
{ "order_id", "0000" },
{ "item_id", "1111" },
{ "item_id", "2222" },
{ null, "skip entry with null key" },
{ "needs escaping", "special chars ? = &" },
{ "skip entry with null value", null }
};
Console.WriteLine(queryParams.ToQueryString());
Output
?order_id=0000&item_id=1111&item_id=2222&needs%20escaping=special%20chars%20%3F%20%3D%20%26
This should work without too much code:
NameValueCollection nameValues = HttpUtility.ParseQueryString(String.Empty);
nameValues.Add(Request.QueryString);
// modify nameValues if desired
var newUrl = "/page?" + nameValues;
The idea is to use HttpUtility.ParseQueryString to generate an empty collection of type HttpValueCollection. This class is a subclass of NameValueCollection that is marked as internal so that your code cannot easily create an instance of it.
The nice thing about HttpValueCollection is that the ToString method takes care of the encoding for you. By leveraging the NameValueCollection.Add(NameValueCollection) method, you can add the existing query string parameters to your newly created object without having to first convert the Request.QueryString collection into a url-encoded string, then parsing it back into a collection.
This technique can be exposed as an extension method as well:
public static string ToQueryString(this NameValueCollection nameValueCollection)
{
NameValueCollection httpValueCollection = HttpUtility.ParseQueryString(String.Empty);
httpValueCollection.Add(nameValueCollection);
return httpValueCollection.ToString();
}
Actually, you should encode the key too, not just value.
string q = String.Join("&",
nvc.AllKeys.Select(a => $"{HttpUtility.UrlEncode(a)}={HttpUtility.UrlEncode(nvc[a])}"));
Because a NameValueCollection can have multiple values for the same key, if you are concerned with the format of the querystring (since it will be returned as comma-separated values rather than "array notation") you may consider the following.
Example
var nvc = new NameValueCollection();
nvc.Add("key1", "val1");
nvc.Add("key2", "val2");
nvc.Add("empty", null);
nvc.Add("key2", "val2b");
Turn into: key1=val1&key2[]=val2&empty&key2[]=val2b rather than key1=val1&key2=val2,val2b&empty.
Code
string qs = string.Join("&",
// "loop" the keys
nvc.AllKeys.SelectMany(k => {
// "loop" the values
var values = nvc.GetValues(k);
if(values == null) return new[]{ k };
return nvc.GetValues(k).Select( (v,i) =>
// 'gracefully' handle formatting
// when there's 1 or more values
string.Format(
values.Length > 1
// pick your array format: k[i]=v or k[]=v, etc
? "{0}[]={1}"
: "{0}={1}"
, k, HttpUtility.UrlEncode(v), i)
);
})
);
or if you don't like Linq so much...
string qs = nvc.ToQueryString(); // using...
public static class UrlExtensions {
public static string ToQueryString(this NameValueCollection nvc) {
return string.Join("&", nvc.GetUrlList());
}
public static IEnumerable<string> GetUrlList(this NameValueCollection nvc) {
foreach(var k in nvc.AllKeys) {
var values = nvc.GetValues(k);
if(values == null) { yield return k; continue; }
for(int i = 0; i < values.Length; i++) {
yield return
// 'gracefully' handle formatting
// when there's 1 or more values
string.Format(
values.Length > 1
// pick your array format: k[i]=v or k[]=v, etc
? "{0}[]={1}"
: "{0}={1}"
, k, HttpUtility.UrlEncode(values[i]), i);
}
}
}
}
As has been pointed out in comments already, with the exception of this answer most of the other answers address the scenario (Request.QueryString is an HttpValueCollection, "not" a NameValueCollection) rather than the literal question.
Update: addressed null value issue from comment.
The short answer is to use .ToString() on the NameValueCollection and combine it with the original url.
However, I'd like to point out a few things:
You cant use HttpUtility.ParseQueryString on Request.RawUrl. The ParseQueryString() method is looking for a value like this: ?var=value&var2=value2.
If you want to get a NameValueCollection of the QueryString parameters just use Request.QueryString().
var nv = Request.QueryString;
To rebuild the URL just use nv.ToString().
string url = String.Format("{0}?{1}", Request.Path, nv.ToString());
If you are trying to parse a url string instead of using the Request object use Uri and the HttpUtility.ParseQueryString method.
Uri uri = new Uri("<THE URL>");
var nv = HttpUtility.ParseQueryString(uri.Query);
string url = String.Format("{0}?{1}", uri.AbsolutePath, nv.ToString());
I always use UriBuilder to convert an url with a querystring back to a valid and properly encoded url.
var url = "http://my-link.com?foo=bar";
var uriBuilder = new UriBuilder(url);
var query = HttpUtility.ParseQueryString(uriBuilder.Query);
query.Add("yep", "foo&bar");
uriBuilder.Query = query.ToString();
var result = uriBuilder.ToString();
// http://my-link.com:80/?foo=bar&yep=foo%26bar
In AspNet Core 2.0 you can use QueryHelpers AddQueryString method.
As #Atchitutchuk suggested, you can use QueryHelpers.AddQueryString in ASP.NET Core:
public string FormatParameters(NameValueCollection parameters)
{
var queryString = "";
foreach (var key in parameters.AllKeys)
{
foreach (var value in parameters.GetValues(key))
{
queryString = QueryHelpers.AddQueryString(queryString, key, value);
}
};
return queryString.TrimStart('?');
}
This did the trick for me:
public ActionResult SetLanguage(string language = "fr_FR")
{
Request.UrlReferrer.TryReadQueryAs(out RouteValueDictionary parameters);
parameters["language"] = language;
return RedirectToAction("Index", parameters);
}
You can use.
var ur = new Uri("/page",UriKind.Relative);
if this nv is of type string you can append to the uri first parameter.
Like
var ur2 = new Uri("/page?"+nv.ToString(),UriKind.Relative);