如何使用 vb.net 的 my.settings 名称和值执行 for 循环? [英] How can i do a for loop with vb.net's my.settings name and value?

问题描述

我需要一些帮助，我试过在谷歌上搜索，也试过在这里搜索但没有成功.

i would like some help with this, i have tried searching on google and have tried searching here with no luck.

到目前为止我尝试过的内容如下:-

what i have tried so far is the following:-

For Each value As Configuration.SettingsPropertyValue In My.Settings.PropertyValues

    Dim myrecord As String = My.Settings.PropertyValues.ToString

    sql_all_matching_records = String.Format("")

Next

但是当我在调试器模式下运行并在 for 循环中放置一个断点时，这会被跳过.

but this just gets skipped when i run in debugger mode and have put a break point within the for loop.

我想要做的是能够遍历 my.settings 中的变量名称，然后获取其值并将其与 SQL 查找进行比较.我唯一挣扎的是遍历 my.settings.

what i want to do is be able to loop through the variable names in my.settings and then take its value and compare it to an SQL lookup. the only thing i am struggling with is looping through the my.settings.

ABOVE 已经得到回答，但是在图片中出现错误，是否写错了代码?不知道我明白什么 vb.net 试图告诉我.我认为这是正确的.

ABOVE has been answered, however getting the error in picture, have a wrote the code wrong? not sure i understand what vb.net is trying to tell me. i thought it was correct.

推荐答案

有点免责声明，我不熟悉如何/何时加载设置以及 PropertyValues 集合被填充，但它似乎不成立直到访问设置值.这是一个奇怪的解决方法，但在循环遍历集合之前从设置中获取一个值似乎可以填充它.您的 InvalidCast 异常发生是因为您试图设置 myrecord = a collection.tostring.我们已经知道集合有多个值，因为我们正在迭代它们，所以我们不能只调用 .tostring .这就像说 Array.ToString()，只是不能那样工作.我认为您实际上正在寻找的是 value.PropertyValue.ToString，它将保存您想要获得的设置值.应用这两项更改后，您会得到:

A bit of a disclaimer, I'm not familiar with how/when settings are loaded and the PropertyValues collection gets filled, but it doesn't seem to hold anything until a settings value is accessed. It's a wierd workaround, but grabbing a value from settings before looping through the collection seems to fill it. Your InvalidCast exception occurs because you're trying to set myrecord = a collection.tostring. We already know that the collection has multiple values because we're iterating them, so we can't just call .tostring on it. That's like saying Array.ToString(), just doesn't work that way. I think what you're actually looking for is value.PropertyValue.ToString, that will hold the settings value you're trying to get. With both those changes applied, you get this:

    Dim dummy As String = My.Settings.dummySetting
    For Each value As System.Configuration.SettingsPropertyValue In My.Settings.PropertyValues

        'Dim myrecord As String = My.Settings.PropertyValues.ToString
        Dim myrecord As String = value.PropertyValue.ToString

        sql_all_matching_records = String.Format("")
    Next

dummySetting 只是我在设置中调用的一个空值.希望这有帮助

The dummySetting is just an empty value that I put in settings to call on. Hope this helps

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