如何在c#的html文件中对表中列的十进制值求和

本文关键字：十进制 求和 文件 html | 更新日期: 2023-09-27 18:15:13

这段代码打算对一列十进制值求和，但在int.Parse()行抛出异常。请参阅这篇文章的末尾，了解我是如何修改代码来纠正这个错误的，以及我在尝试中收到的错误。

    static void Main()
    {
        String htmlFile = "C:/Temp/Test11.html";
        HtmlDocument doc = new HtmlDocument();
        doc.Load(htmlFile);
    // Site Collection Storage Used (GB)
    var sum = doc.DocumentNode.SelectSingleNode("//table")
        // The sum will be of the row elements
        .Elements("tr")
        // Skip this many rows from the top
        .Skip(1)
        // .ElementAt(2) = third column
        // .Last() = last column
        .Sum(tr => int.Parse(tr.Elements("td").ElementAt(3).InnerText)); 
    Console.WriteLine("Site Collection Storage Used (GB): " + sum);
        Console.ReadLine();
    }

这里有一个例外:

System.FormatException was unhandled
  HResult=-2146233033
  Message=Input string was not in a correct format.
  Source=mscorlib
  StackTrace:
       at System.Number.StringToNumber(String str, NumberStyles options, NumberBuffer& number, NumberFormatInfo info, Boolean     parseDecimal)
       at System.Number.ParseInt32(String s, NumberStyles style, NumberFormatInfo info)
       at System.Int32.Parse(String s)
       at ValueSpecifiedCellSpecifiedTable.Program.<Main>b__2(HtmlNode tr) in c:'Users'User1'Documents'Visual Studio     2012'Projects'_ValueSpecifiedCellSpecifiedTable'ValueSpecifiedCellSpecifiedTable'Program.cs:line 92
       at System.Linq.Enumerable.WhereSelectEnumerableIterator`2.MoveNext()
       at System.Linq.Enumerable.Sum(IEnumerable`1 source)
       at System.Linq.Enumerable.Sum[TSource](IEnumerable`1 source, Func`2 selector)
       at ValueSpecifiedCellSpecifiedTable.Program.Main() in c:'Users'User1'Documents'Visual Studio 2012'Projects    '_ValueSpecifiedCellSpecifiedTable'ValueSpecifiedCellSpecifiedTable'Program.cs:line 85
       at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
       at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
       at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
       at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
       at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state,     Boolean preserveSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean     preserveSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Threading.ThreadHelper.ThreadStart()
  InnerException:

我尝试用Decimal.Parse()替换int.Parse()，但它告诉我:

"Error  1   Cannot implicitly convert type 'decimal' to 'int'. An explicit conversion exists (are you missing a cast?)      C:'Users'hptSetupAdmin'Documents'Visual Studio 2012'Projects'_ValueSpecifiedCellSpecifiedTable'ValueSpecifiedCellSpecifiedTable    'Program.cs  92  17  ValueSpecifiedCellSpecifiedTable

将int.Parse()更改为Decimal.Parse()后，我看不到哪里有int要转换。

请帮我用这个代码来实现我的目标。

这里是html文件供参考:

<html>
<head>
<title>Tables</title>
</head>
<body>
<table border="1">
  <tr>
    <th>Environment</th>
    <th>Databases</th>
    <th>Sites</th>
    <th>Site Collection Storage Used (GB)</th>
    <th>Ref</th>
 </th>
  </tr>
  <tr>
    <td>Public</td>
    <td>14</td>
    <td>28</td>
    <td>32.6602</td>
    <td>2</td>
  </tr>
  <tr>
    <td>Local</td>
    <td>5</td>
    <td>8</td>
    <td>7.0302</td>
    <td>3</td>
  </tr>
  <tr>
    <td>Shared</td>
    <td>6</td>
    <td>9</td>
    <td>17.092</td>
    <td>9</td>
  </tr>
</table>

如何在c#的html文件中对表中列的十进制值求和

转换几乎肯定在LINQ语句之外:如果sum是int类型，则需要显式强制转换。将sum声明为小数或插入显式强制转换可以解决这个问题:

    // Site Collection Storage Used (GB)
    sum = (int)doc.DocumentNode.SelectSingleNode("//table")
        // The sum will be of the row elements
        .Elements("tr")
        // Skip this many rows from the top
        .Skip(1)
        // .ElementAt(2) = third column
        // .Last() = last column
        .Sum(tr => decimal.Parse(tr.Elements("td").ElementAt(3).InnerText)); 
    Console.WriteLine("Site Collection Storage Used (GB): " + sum);

这里是一个链接到ideone上的快速演示(这是不可能使用HTML敏捷包在ideone上，所以我复制你的数据到字符串数组)。

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