VB.Net Nested嵌套循环
VB.Net 循环VB.Net允许在另一个循环内使用一个循环。 以下部分显示了几个例子来说明这个概念。
语法：
VB.Net中嵌套For循环语句的语法如下：
For counter1 [ As datatype1 ] = start1 To end1 [ Step step1 ] For counter2 [ As datatype2 ] = start2 To end2 [ Step step2 ] ... Next [ counter2 ] Next [ counter 1]
VB.Net中嵌套While循环语句的语法如下：
While condition1 While condition2 ... End While End While
VB.Net中嵌套Do ... While循环语句的语法如下：
Do { While | Until } condition1 Do { While | Until } condition2 ... Loop Loop
关于循环嵌套的最后一点是，你可以把任何类型的循环放在任何其他类型的循环里面。 例如，for循环可以在while循环内，反之亦然。
示例：
以下程序使用嵌套for循环来查找从2到100的素数：
Module loops Sub Main() ' local variable definition Dim i, j As Integer For i = 2 To 100 For j = 2 To i ' if factor found, not prime If ((i Mod j) = 0) Then Exit For End If Next j If (j > (i j)) Then Console.WriteLine("{0} is prime", i) End If Next i Console.ReadLine() End Sub End Module
当上述代码被编译和执行时，它产生以下结果：
2 is prime 3 is prime 5 is prime 7 is prime 11 is prime 13 is prime 17 is prime 19 is prime 23 is prime 29 is prime 31 is prime 37 is prime 41 is prime 43 is prime 47 is prime 53 is prime 59 is prime 61 is prime 67 is prime 71 is prime 73 is prime 79 is prime 83 is prime 89 is prime 97 is prime
