VB.NET String Length Example

Use the Length property on a String. Describe the performance of accessing Length.

String Length. How many characters are contained in your VB.NET String? With the Length property on the String type, you can determine this count fast.

Length is useful in many VB.NET programs. Its implementation is also interesting to examine. We explore the performance accessing Length in a for-loop.Loop Over String

This program shows the Length property in action. The length of the String "dotnet" is found to be 6 characters. After another 5 characters are appended, the length is now 11 characters.

Immutable: A String cannot be directly changed. So when "Codex" is appended to the String, a whole new String is created.

Strings

And: During String creation, the length value is stored. The String will thus always have the same length.

VB.NET program that uses Length property Module Module1 Sub Main() ' Get length of string. Dim value As String = "dotnet" Dim length As Integer = value.Length Console.WriteLine("{0}={1}", value, length) ' Append a string. ' ... Then get the length of the newly-created string. value += "Codex" length = value.Length Console.WriteLine("{0}={1}", value, length) End Sub End Module Output dotnet=6 dotnetCodex=11

Performance. A String's length could be computed once and stored as a field. Or it could be calculated in a loop every time the property is accessed.Property

Important: In VB.NET, the value is stored, which makes getting the length of any string equally fast.

However: If the Length were to be computed each time, a loop over every character that tested against the bound Length would be slow.

And: The developer would have to cache the value. This code is not necessary in VB.NET.

Performance, for-loop. It is typically faster to use Length directly in the bounds of a for-loop. The JIT compiler can make optimizations to help char access.

Note: We run a benchmark that tests Length access in a for-loop. Using a "length" local does not help performance.

A summary. The Length is computed whenever a String is created. When you access Length, characters are not counted: instead the cached value is returned.

We examined Length from a conceptual perspective. Dynamically computing the Length could cause a performance nightmare. But this is not a problem in VB.NET.

The Dev Codes

.Net

.NET Array Dictionary List String 2D Async DataTable Dates DateTime Enum File For Foreach Format IEnumerable If IndexOf Lambda LINQ Parse Path Process Property Regex Replace Sort Split Static StringBuilder Substring Switch Tuple

Java

Core Array ArrayList HashMap String 2D Cast Character Console Deque Duplicates File For Format HashSet If IndexOf Lambda Math ParseInt Process Random Regex Replace Sort Split StringBuilder Substring Switch Vector While

Related Links

Adjectives Ado Ai Android Angular Antonyms Apache Articles Asp Autocad Automata Aws Azure Basic Binary Bitcoin Blockchain C Cassandra Change Coa Computer Control Cpp Create Creating C-Sharp Cyber Daa Data Dbms Deletion Devops Difference Discrete Es6 Ethical Examples Features Firebase Flutter Fs Git Go Hbase History Hive Hiveql How Html Idioms Insertion Installing Ios Java Joomla Js Kafka Kali Laravel Logical Machine Matlab Matrix Mongodb Mysql One Opencv Oracle Ordering Os Pandas Php Pig Pl Postgresql Powershell Prepositions Program Python React Ruby Scala Selecting Selenium Sentence Seo Sharepoint Software Spellings Spotting Spring Sql Sqlite Sqoop Svn Swift Synonyms Talend Testng Types Uml Unity Vbnet Verbal Webdriver What Wpf

TheDeveloperBlog.com

VB.NET String Length Example

Related Links:

.Net

Java

Related Links