I tried something like this
#Html.DisplayFor(modelItem => (item.Name + "#" + item.Department))
I get "InvalidOperationException" (Templates can be used only with field access, property access, single-dimension array index, or single-parameter custom indexer expressions.)
Both the members are strings, I thought this should work...
Thanks
The error is because DisplayFor accepts an Expression which is Expression<Func<TModel,TReturn>> and not a delegate Func<TModel, TReturn>. So you can't mix it with random C# code as it is not a delegate.
To get what you want, you can use this (odd syntax I know - because you have to escape the #):
#Html.DisplayFor(item => item.Name)#:###Html.DisplayFor(item => item.Department)
Refer the below links.I Hope this will solve your problem.
Get a template error when I try to do this?
Templates can be used only with field access, property access, single-dimension array index, or single-parameter custom indexer expressions
Related
I am filtering PrimeFaces DataTables using dynamic filters.I have this working using Spring org.springframework.data.jpa.domain.Specification.Now I am wondring how to do the same using QueryDSL.
Using specification I can use javax.persistence.criteria.Root to get a javax.persistence.criteria.Join, use javax.persistence.criteria.Expression.as(Class<String> type) to cast it to String and finally use javax.persistence.criteria.CriteriaBuilder.like(Expression<String> x, String pattern, char escapeChar).
How do I do the same in QueryDSL ? I can get PathBuilder using new PathBuilder<T>(clazz, "entity") (do you really have to use the variable here? I would like my class to be generic...) but then the com.mysema.query.types.path.PathBuilder.get(String property) returns new PathBuilder instead of an Expression.
If I try to use com.mysema.query.types.path.PathBuilder.getString(String property) I get java.lang.IllegalArgumentException: Parameter value [1] did not match expected type [java.lang.Integer].
Seems like the part I am missing is the cast.
I'm quite sure someone was dealing with the same thing already.
Thanks.
Edit: Stack trace for IllegalArgumentException
Trying to search for text "1" inside integer column using com.mysema.query.types.path.PathBuilder.getString(String property) - that's where I need the cast to happen :
Caused by: java.lang.IllegalArgumentException: Parameter value [1] did not match expected type [java.lang.Integer]
at org.hibernate.ejb.AbstractQueryImpl.validateParameterBinding(AbstractQueryImpl.java:375)
at org.hibernate.ejb.AbstractQueryImpl.registerParameterBinding(AbstractQueryImpl.java:348)
at org.hibernate.ejb.QueryImpl.setParameter(QueryImpl.java:375)
at org.hibernate.ejb.QueryImpl.setParameter(QueryImpl.java:442)
at org.hibernate.ejb.QueryImpl.setParameter(QueryImpl.java:72)
at com.mysema.query.jpa.impl.JPAUtil.setConstants(JPAUtil.java:44)
at com.mysema.query.jpa.impl.AbstractJPAQuery.createQuery(AbstractJPAQuery.java:130)
at com.mysema.query.jpa.impl.AbstractJPAQuery.createQuery(AbstractJPAQuery.java:97)
at com.mysema.query.jpa.impl.AbstractJPAQuery.list(AbstractJPAQuery.java:240)
at org.springframework.data.jpa.repository.support.QueryDslJpaRepository.findAll(QueryDslJpaRepository.java:102)
...
To get a valid condition you will need to take the types of the properties into account, e.g.
pathBuilder.getNumber(Integer.class, property).stringValue().like(likePattern)
I was researching a similar topic until I came across this aged question. I hope my answer will be helpful to some.
I think the possible solution lies (exclusively) outside of QueryDSL. You can use common Java reflection to obtain the field type, something like
Class type = clazz.getDeclaredField(criteria.getKey()).getType();
// don't forget to catch exception if field doesn't exist ..
switch(type.getSimpleName()) {
case "String":
StringExpression exp = entityPath.getString(...);
}
That way you can have a reasonably dynamic implementation.
I'm using VB.Net and I would like to know how to get the selected checkboxes in a checkboxlist using linq and lambda syntax (not query syntax, repeat NO query syntax).
I tried this but it's definitely not right.
cblRequired.Items.OfType(Of ListItem).Where(Function (i As ListItem ) i.Selected End Function)
I believe that the only thing wrong with your code is that you should not have the End Function, since it's a single-line lambda expression. This should work:
cblRequired.Items.OfType(Of ListItem).Where(Function(i As ListItem) i.Selected)
Technically, you don't need to specify the type of i, since it will automatically infer the type:
cblRequired.Items.OfType(Of ListItem).Where(Function(i) i.Selected)
If you want it to be a multi-line lamba expression, that would look like this:
cblRequired.Items.OfType(Of ListItem).Where(Function(i)
Return i.Selected
End Function)
I've made a program that uses reflection to add Traits dynamically, and solves conflicts automatically in one predeterminated way.
It uses aliases. It's working (I think), but I have only a problem when finally adding the trait.
My program generates all the aliases for each conflicting method, and add them with the trait to the class. The problem is that I'm not able to generate the selector correctly, its generating a string instead.
For example:
I need this
TCircle # {#circleHash -> #hash}
but I'm generating this
TCircle # {'#circleHash' -> #hash}
you can see the quotes in #circleHash.
Because is a meta-program, it generates also dynamically the selector.
How I can get it without the quotes and with the #?
I need to able to do something like this
"have the selector name in string"
obj := 'SelectorDinamicallyGenerated'.
^(#obj)
and get #SelectorDinamicallyGenerated, and not '#SelectorDinamicallyGenerated'.
How can I do this?
I've tried doing like that (#obj) but it is not working (getting #obj)
I've found it.
It's
obj asSymbol
Good you found it yourself. Maybe it is just irritating that in smalltalk a symbol is a selector. It is just not the case that there is a selector class and you could do "aString asSelector". So
'foo' asSymbol => #foo
will do. If you need to generate a setter you can do
'foo' asSymbol asMutator => #foo:
Dojo's dijit html5 tags use an attribte name data-dojo-props. The value is basically a JSON string without quotes around the property names and without the outermost braces.
It looks something like this.
data-dojo-props="prop1:'xyz', prop2:true, prop3: { subprop1: 1, subprop2: 'abc'}"
I'm using C# to write this out from a C# object using JSON.NET and passing in the object pointer. I found settings to leave out the property name quotes, but I can't figure out a graceful way to remove the outside braces.
For now, I'll run the string through a regex to remove them, but was wondering if someone new a better way.
I serialize each top level property separately and make it a global javascript variable. I then reference that variable in data-dojo-props. I admit it's not that elegant.
My concern with your approach above, is if the value of subprop2 contains a quote, you will get a parser error.
<script type="text/javascript">
menuData = {THE SERIALIZED JSON GOES HERE};
</script>
<div data-dojo-type="SomeWidget" data-dojo-props="menuData: menuData"></div>
I want to pass hashset to ActiveRecord finder method Model_name.where({ :key => value }). This works perfectly, but SQL composed from that uses straight comparison =. Is it possible to customize this and switch to LIKE comparison usage with hashset?
The :key => value syntax only works for =, IN, and BETWEEN conditions (depending on whether value is atomic, an Array, or a Range). Anything else requires you to pass the SQL as a string:
Model.where("key LIKE ?", value)