我该怎么解决这个系统.invalidcastexception未处理？ [英] How can I solve this system.invalidcastexception was unhandled?

问题描述

我有一个WPF DataGrid来显示PostgreSQL数据。它显示一个包含14行的数据表。它是服务器的外部连接，列数根据用户参数不断变化。我创建了一个名为UCS1freqs的类，我用它来设置数据的频率值，以便稍后将这些值绘制成散点图。问题是，一旦它收集了所有数据，它就会给我一个无效的强制转换异常未处理（无法将类型为

MS.Internal.NamedObject的对象转换为类型System.Data.DataRowView）。我知道问题与我使用DataRowView有关。我是新手代码，对WPF来说肯定是新手。非常感谢任何帮助



我尝试过：



var ucs1Freqs = new List

I have a WPF DataGrid to display PostgreSQL data. It displays a data table with 14 rows. It is an external connection to server and the number of columns change constantly depending on the user parameters. I have created a class called UCS1freqs and I use it to set the frequency values from data for later plotting those values into a scatter chart. The problem is that once it collects all the data it gives me a invalid cast Exception was unhandled (Unable to cast object of type
MS.Internal.NamedObject to type System.Data.DataRowView). I know the problem is related to me using DataRowView. I'm new to code and definitely new to WPF. Any help is greatly appreciated

What I have tried:

var ucs1Freqs = new List

推荐答案

这是我的问题代码



var ucs1Freqs = new List< Ucs1Freq>（）;



foreach（DataGrid1.Items中的DataRowView行）

{

if（转换） .ToDouble（row.Row.ItemArray [11]）== 28.464258839）

{

var Ucs1freqstring = row.Row.ItemArray [0] .ToString（）; < br $>


row.Row.ItemArray [0] = Ucs1freqstring;

Ucs1Freq tempFreq = new Ucs1Freq（）;

tempFreq.Frequency = Ucs1freqstring;

ucs1Freqs.Add（tempFreq）;



}



}

this is the code from my question

var ucs1Freqs = new List<Ucs1Freq>();

foreach (DataRowView row in DataGrid1.Items)
{
if (Convert.ToDouble(row.Row.ItemArray[11]) == 28.464258839)
{
var Ucs1freqstring = row.Row.ItemArray[0].ToString();

row.Row.ItemArray[0] = Ucs1freqstring;
Ucs1Freq tempFreq = new Ucs1Freq();
tempFreq.Frequency = Ucs1freqstring;
ucs1Freqs.Add(tempFreq);

}

}

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