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Skip While Clause (Visual Basic)

Bypasses elements in a collection as long as a specified condition is true and then returns the remaining elements.

Syntax

Skip While expression  

Parts

Term Definition
expression Required. An expression that represents a condition to test elements for. The expression must return a Boolean value or a functional equivalent, such as an Integer to be evaluated as a Boolean.

Remarks

The Skip While clause bypasses elements from the beginning of a query result until the supplied expression returns false. After expression returns false, the query returns all the remaining elements. The expression is ignored for the remaining results.

The Skip While clause differs from the Where clause in that the Where clause can be used to exclude all elements from a query that do not meet a particular condition. The Skip While clause excludes elements only until the first time that the condition is not satisfied. The Skip While clause is most useful when you are working with an ordered query result.

You can bypass a specific number of results from the beginning of a query result by using the Skip clause.

Example

The following code example uses the Skip While clause to bypass results until the first customer from the United States is found.

Public Sub SkipWhileSample()
    Dim customers = GetCustomerList()

    ' Return customers starting from the first U.S. customer encountered.
    Dim customerList = From cust In customers
                       Order By cust.Country
                       Skip While IsInternationalCustomer(cust)

    For Each cust In customerList
        Console.WriteLine(cust.CompanyName & vbTab & cust.Country)
    Next
End Sub

Public Function IsInternationalCustomer(ByVal cust As Customer) As Boolean
    If cust.Country = "USA" Then Return False

    Return True
End Function

See also