Szerkesztés

Megosztás a következőn keresztül:

Strings.Left(String, Int32) Method

  • Reference

Definition

Namespace:
Microsoft.VisualBasic
Assembly:
Microsoft.VisualBasic.Core.dll
Assembly:
Microsoft.VisualBasic.dll
Source:
Strings.vb
Source:
Strings.vb
Source:
Strings.vb

Returns a string containing a specified number of characters from the left side of a string.

public:
 static System::String ^ Left(System::String ^ str, int Length);
public static string Left (string? str, int Length);
public static string Left (string str, int Length);
static member Left : string * int -> string
Public Function Left (str As String, Length As Integer) As String

Parameters

str
String

Required. String expression from which the leftmost characters are returned.

Length
Int32

Required. Integer expression. Numeric expression indicating how many characters to return. If 0, a zero-length string ("") is returned. If greater than or equal to the number of characters in str, the entire string is returned.

Returns

String

A string containing a specified number of characters from the left side of a string.

Exceptions

ArgumentException

Length < 0.

Examples

This example demonstrates the use of the Left function to return a substring of a given String. In a class that has a Left property, it may be necessary to fully qualify the Left function.

Dim testString As String = "Hello World!"
' Returns "Hello".
Dim subString As String = Left(testString, 5)

Remarks

To determine the number of characters in str, use the Len function. If used in a Windows Forms application, or any other class that has a Left property, you must fully qualify the function with Microsoft.VisualBasic.Left.

Note

The LeftB function in previous versions of Visual Basic returns a string in bytes rather than characters. It is used primarily for converting strings in double-byte character set (DBCS) applications. All current Visual Basic strings are in Unicode, and LeftB is no longer supported.

Applies to

See also