c# - After setting selectedindex, click on control with mouse shows wrong item -

-

the engineers requested combobox numbers 500 -500 (negative numbers listed @ bottom, not alphabetical).

they requested being able type in number in combo jump correct item.

problem: type in "44", tab away. click on control mouse , can see "449" selected.

here complete code:

using system; using system.collections.generic; using system.componentmodel; using system.data; using system.drawing; using system.linq; using system.text; using system.threading.tasks; using system.windows.forms;  namespace combotest {     public partial class form1 : form     {         public form1()         {             initializecomponent();         }          private void form1_load(object sender, eventargs e)         {             (int = 500; > -500; i--)             {                 combobox1.items.add(i.tostring());             }         }          private void combobox1_leave(object sender, eventargs e)         {             combobox1.selectedindex = combobox1.findstringexact(combobox1.text);         }     } }

no problem! tell myself. findstringexact finding first alpha match. replace leave event code loop:

using system; using system.collections.generic; using system.componentmodel; using system.data; using system.drawing; using system.linq; using system.text; using system.threading.tasks; using system.windows.forms;  namespace combotest {     public partial class form1 : form     {         public form1()         {             initializecomponent();         }          private void form1_load(object sender, eventargs e)         {             (int = 500; > -500; i--)             {                 combobox1.items.add(i.tostring());             }         }          private void setcombo(string value)         {             combobox1.items.clear();              int myindex = -1;             (int = 500; > -501; i--)             {                 myindex += 1;                  combobox1.items.add(i.tostring());                 if (i.tostring().trim() == value.trim())                 {                     combobox1.selectedindex = myindex;                 }             }         }          private void combobox1_leave(object sender, eventargs e)         {            // combobox1.selectedindex = combobox1.findstringexact(combobox1.text);             setcombo(combobox1.text);          }     } }

i try again , still when click mouse on combo after typing in "44" , tabbing away, "449" selected instead.

because of way you're populating combobox, 449 occurs earlier in list 44, , it's selected first (it's first closest match user typing). desired behavior, you'd have have 2 lists - 1 goes 0 500 , goes 0 -500.

instead, use numericupdown box , set maximum property 500 , minimum value -500. ensure user can enter number falls within specified range.


Comments

Post a Comment

Popular posts from this blog

c# - How Configure Devart dotConnect for SQLite Code First? -

-
can configure following sample code ? when run following code, error : no entity framework provider found ado.net provider invariant name 'devart.data.sqlite' setting in machine.config <system.data> <dbproviderfactories> <add name="dotconnect sqlite" invariant="devart.data.sqlite" description="devart dotconnect sqlite" type="devart.data.sqlite.sqliteproviderfactory, devart.data.sqlite, version=4.6.287.0, culture=neutral, publickeytoken=09af7300eec23701" /> </dbproviderfactories> </system.data> after add below block code in app.config <?xml version="1.0"?> <configuration>   <configsections> <!-- more information on entity framework configuration, visit http://go.microsoft.com/fwlink/?linkid=237468 --> <section name="entityframework" type="system.data.entity.internal.configfile.entityframeworksection, entit...
Read more

java - Copying object fields -

-
what best way of copying classes when need have 2 independent variables? have simple class: public class myclass { boolean = false; string b= "not empty"; } do need make method : assign(myclass data ) { a= data.a; b= data.b; } is there automatic method copy (duplicate) objects in java? do need make method : pretty close. instead of making method, should make constructor. such constructors called copy constructor , , create them this: myclass(myclass data) { = data.a; b = data.b; } and create copy of instance, use constructor this: myclass obj1 = new myclass(); myclass obj2 = new myclass(obj1); copy constructor can tedious : using copy constructor create deep-copy can tedious, when class has mutable fields. in case, assignment create copy of reference, , not object itself. have create copy of fields (if want deep copy). can go recursive. a better way create deep copy serialize , deserialize object. why not use clone()? ...
Read more

c++ - Clear the memory after returning a vector in a function -

-
i have function processes , stores lot of data in , returns results vector of class. amount of data stored in function tremendous , want clear storage memory of function after finished job. necessary (does function automatically clear memory) or should clear memory function? update: vector<customers> process(char* const *filename, vector<int> id) { vector<customers> list_of_customers; (perform actions) return list_of_customers; } variables defined locally within function automatically released @ end of function scope. destructors objects called, should free memory allocated objects (if objects coded correctly). example of such object std::vector . anything you've allocated new must have corresponding delete release storage. try avoid doing own allocation , use raii instead, i.e. containers or smart pointers.
Read more