mysql - VB.Net不使用数据库数据填充数组

我想用mysql数据库中的数据填充数组

这是我的代码

Dim DataBlob As String()
        Dim Count As Integer

        While READER.Read
            Count += 1
            Dim eName As String = READER(1)
            Dim eSname As String = READER(2)
            Dim eID As String = READER(0)

            DataBlob(Count) = eSname + eName

        End While

        Return DataBlob

但我看不到任何退货。可能是什么问题

注意：有警告说明：DataBlob is used before a value is assigned

最佳答案

如果要使用数组，只需将计数设为1st

Dim Count as integer=reader_count(0)
Dim DataBlob(count-1) As String
'subtract 1 b/c array starts at zero
Dim i as integer=0
While READER.Read
        Dim eName As String = READER(1)
        Dim eSname As String = READER(2)
        Dim eID As String = READER(0)
        DataBlob(i) = eSname + eName
        i+=1
End While

另一种选择是，如果您知道数量有限（假设您总是在阅读器中拉动“世界各国”，则可能会高估），然后在完成后重新排列数组，但必须使用preserve。除非您要处理小型阵列，否则我不会这样做。

'there is no way the reader will return more than 500
Dim DataBlob(500) As String
While READER.Read
        Count += 1
        Dim eName As String = READER(1)
        Dim eSname As String = READER(2)
        Dim eID As String = READER(0)
        DataBlob(Count) = eSname + eName
End While
ReDim Preserve DataBlob(Count)

关于mysql - VB.Net不使用数据库数据填充数组，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/46808641/