Skip to main content

How to use ComboBox in windows forms application c#

ComboBox in windows forms application -Introduction

A ComboBox display a editable TextBox with ListBox. You can select item from the list also you can search item by using TextBox. The default style of ComboBox is drop-down list. You can change the style of ComboBox with the help of DropDownStyle property. That property contain three enumerated value, If you select Dropdown list box then you can not edit text portion. Now, take a simple example to add items in the Combo Box-please see the video



Video contains different ways to add item in the ComboBox like, using show smart tag, items property, add item at run time using add method.
For adding items at run time in ComboBox:
 comboBox1.Items.Add(String text);
If you want to change the DropdownStyle at design as well as run time- please see the following video:


I you want to access or retrieve selected item from the comboBox then see this video. In this video i have a comboBox with some fruit items and a button control. When we press the button then selected item show in the messageBox.
Note : If you have to press buton without select any item then get the error message. Video also solve this problem with the help of selectedIndex property. So in this video you will see the example of SelectedIndex property.

 Now, come to the DataSource property of comboBox. Bind the combobox with the class and enumeration type. Video contain example of both type.


If you want to add thousand of item without any intrupt then use beginUpdate() and EndUpdate() method of it. This video contain example of both, also contain findString method example.

Comments

Popular posts from this blog

difference between structure and union in C Language

In c language article we will see the difference between union and structure. Both are the user define datatype in c language. See the table which is mentioned below: ASP.NET Video Tutorial Series Structure Union1.The keywordstruct is used to define a structure 1. The keyword union is used to define a union. 2. When a variable is associated with a structure, the compiler allocates the memory for each member. The size of structure is greater than or equal to the sum ofsizes of its members. The smaller members may end with unused slack bytes. 2. When a variable is associated with a union, thecompiler allocates thememory by considering the size of the largest memory. So, size of union is equal to the size of largest member. 3. Each member within a structure is assigned unique storage area of location. 3. Memory allocated is shared by individual members of union. 4. The address of each member will be in ascending order This indicates that memory for each member will start at different offset v…

Difference between Linear search and Binary Search in c language

SQL Video Channel : Download all SQL Video



Binary Search Linear Search Works only on sorted items. such as  1,2,3,4,5,6  etc
Works on sorted as well as unsorted items. 12,4,5,3,2,1 etc Very efficient if the items are sorted Very efficient if the items are less and present in the beginning of the list. such as Suppose your list items are : 12,3,4,5,1 and you want to search 12 number then you get beginning in the list. Works well with arrays and not on linked lists. Works with arrays and linked lists.
Number of comparisons are less More number of comparisons are required if the items are present in the later part of the array or its elements are more.

Memory representation of Linked List Data Structures in C Language

Memory representation of Linked List

             In memory the linked list is stored in scattered cells (locations).The memory for each node is allocated dynamically means as and when required. So the Linked List can increase as per the user wish and the size is not fixed, it can vary.

               Suppose first node of linked list is allocated with an address 1008. Its graphical representation looks like the figure shown below:


      Suppose next node is allocated at an address 506, so the list becomes,



  Suppose next node is allocated with an address with an address 10,s the list become,


The other way to represent the linked list is as shown below:




 In the above representation the data stored in the linked list is “INDIA”, the information part of each node contains one character. The external pointer root points to first node’s address 1005. The link part of the node containing information I contains 1007, the address of next node. The last node …