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vb.net 如何对数据库查询结果记录集排序？
加了单引号就是一个常量字符串了，对于每一行都是一样的
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像这种放在最前面的字段，order by 1 就可以了
VB.NET 程序 随机产生10个整数并进行排序
Public Class Form1
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim N As Integer = 9
Randomize()
Dim xx(9) As Integer
For i As Integer = 0 To N
xx(i) = Int(Rnd() * 1000) '产生 [0,1000) 之间的整数
Next
For i As Integer = 0 To N - 1
For j As Integer = i + 1 To N
If xx(i) xx(j) Then
Dim temp As Integer = 0
temp = xx(i) : xx(i) = xx(j) : xx(j) = temp
End If
Next
Next
Dim sum As Integer = 0
For i As Integer = 0 To N
TextBox1.Text += xx(i) vbCrLf
sum += xx(i)
Next
TextBox1.Text += "最大值：" xx(9) vbCrLf "最小值：" xx(0) vbCrLf "平均值：" sum / 10
End Sub
End Class
VB.NET中数据的排序问题
建议用 DataGridView（你用的是它吧？）内建的排序方法来排序。介绍和示例代码可以参考MSDN：
vb.net 排列组合 代码
第一题:
不需要任何控件,代码如下:
Private Sub Form_Click()
Dim A() As Integer, N As Integer
Dim St As String, I As Integer, J As Integer
Randomize
Do
St = InputBox("数字的个数", "输入", Int(Rnd * 100))
If St = "" Then
MsgBox "请输入数字!"
Else
N = Int(Val(St))
If N 1 Then
MsgBox "请输入大于0的数字!"
Else
Exit Do
End If
End If
Loop
ReDim A(N)
For I = 1 To N
Do
St = InputBox("第" + Str(I) + "个数字", "输入", Int(Rnd * 100))
If St = "" Then
MsgBox "请输入数字!"
Else
A(I) = Int(Val(St))
Exit Do
End If
Loop
Next
For I = 1 To N - 1
For J = I + 1 To N
If A(I) A(J) Then
A(0) = A(I)
A(I) = A(J)
A(J) = A(0)
End If
Next
Next
For I = 1 To N
Open App.Path "\" Trim(Str(I)) ".txt" For Output As #1
Print #1, A(I)
Close #1
Next
Print "已经把"; N; "个数写入到"; App.Path; "\1.txt 到 "; N; ".txt中.请查看."
End Sub
'已经运行过.
第二题:
DIM 是变量声明语句,它的格式为:
dim 变量名[as 格式] [,变量名[as 格式][,变量名[as 格式]......]
其中:
变量名:以字母或汉字开始的字串,代表一个变量
格式有以下几种:
属于数字的有五种:
(1)字节型:byte可取值0-255
(2)整形:integer可取值-32768至32767
(3)长整形:long(可取值范围很大的正负整数)
(4)单精度型:single(可取值小数)
(5)双精度型:double(可取值范围更大,小数位数更多的小数)
字符串型:string(可代表由字母\数字或汉字组成的字符集合)
布尔型:boolean(取值为ture\false)
日期型:date(可表示形如2009-5-26 02:36这样的组合)
如果要用姓名\住址\单位名称...等用字符串型(string)
eg:dim name as string(用name变量表示名字时,声明成字符串变量)
如果是用数字需要做计算,如工资\合计\人数....等要用数字型,但有一个原则,优先选用范围小的(按照字节型(byte)\整形(integer)\长整形(long)\单精度型(single)\双精度型(double)的顺序选择),够用就可以了,这样可以占用内存少,运算速度快.
eg:dim count as integer(用integer表示员工人数时,可声明成整形变量)
eg:dim sum as single(用sum表示工资时,可声明成单精度型变量)
不知是否说得清楚了.
VB.net 数组怎么按任意元素的顺序排序输出
你直接传一个数组进去，而且是一个结构体数组，array.sort怎么知道根据结构中的哪一个属性进行排序？放一个c#的代码你看看，VB和C#很相似的
class Program
{
static void Main(string[] args)
{
People[] p = new People[3]
{
new People{name="张三"},
new People{name="李四"},
new People{name="张二名"}
};
//重点传一个实现了IComparer接口的类进去，告诉Array.Sort怎么排序
Array.Sort(p, new PeopleCompare());
foreach (var item in p)
{
Console.WriteLine(item.name);
}
Console.ReadKey();
}
}
//People结构体，换成类一样的
public struct People
{
public string name { get; set; }
}
//实现了IComparer接口的类
public class PeopleCompare : IComparer
{
public int Compare(object x, object y)
{
People p1 = (People)x ;
People p2 = (People)y;
return p1.name.CompareTo(p2.name);
}
}
VB.NET 2维数组排序排序和赋值问题
窗体上添加3个标签，1个按钮，在按钮的单击事件里写代码，如下：
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim a(,) As Integer = {{5, 6}, {1, 3}, {8, 9}, {72, 1}, {63, 4}}
Dim Temp As Integer
Dim i As Integer
Dim j As Integer
Dim x As Integer
Dim y As Integer
'显示排序前的数据
Label1.Text = "排序前数据：" vbCrLf
For i = 0 To 4
Label1.Text = Label1.Text a(i, 0) " " a(i, 1) vbCrLf
Next
For i = 0 To 3
For j = i + 1 To 4
If a(i, 0) a(j, 0) Then
Temp = a(i, 0)
a(i, 0) = a(j, 0)
a(j, 0) = Temp
Temp = a(i, 1)
a(i, 1) = a(j, 1)
a(j, 1) = Temp
End If
Next
Next
'显示排序前的数据
Label2.Text = "排序后数据：" vbCrLf
For i = 0 To 4
Label2.Text = Label2.Text a(i, 0) " " a(i, 1) vbCrLf
Next
'把第3行元素赋予X,Y
x = a(2, 0)
y = a(2, 1)
'输出X,Y
Label3.Text = "X=" x vbCrLf "Y=" y
End Sub
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