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POWhy are two nearly identical DataSets behaving different?
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  1. POWhy are two nearly identical DataSets behaving different?
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    copied!<p>i've got two DataSet with each one DataTable inside.</p> <p>DataSet #1:</p> <pre><code> DataTable table = new DataTable(name); table.Columns.Add("ID", typeof(int)); table.Columns.Add("Customer Name",typeof(string)); table.Columns.Add("Contact Name", typeof(string)); table.Columns.Add("Adress", typeof(string)); table.Columns.Add("City", typeof(string)); table.Columns.Add("Postal Code", typeof(string)); table.Columns.Add("Country", typeof(string)); string mem; Console.Clear(); Console.WriteLine("| {0} | {1} | {2} | {3} | {4} | {5} |", table.Columns[1], table.Columns[2], table.Columns[3], table.Columns[4], table.Columns[5], table.Columns[6]); int count=1; do { table.Rows.Add(count, Console.ReadLine(), Console.ReadLine(), Console.ReadLine(), Console.ReadLine(), Convert.ToInt32(Console.ReadLine()), Console.ReadLine()); Console.WriteLine("if finished, type end"); mem=Console.ReadLine(); count++; } while (mem != "end"); DataSet set = new DataSet(); set.Tables.Add(table); </code></pre> <p>and DataSet #2:</p> <p>("load" is DataSet #1)</p> <pre><code> string srch = Console.ReadLine(); string ask = "[Customer Name] like '%"+srch+"%' OR [Contact Name] like '%"+srch+"%' OR [Adress] like '%"+srch+"%' OR [City] like '%"+srch+"%' OR [Postal Code] like '%"+srch+"%' OR [Country] like '%"+srch+"%'"; DataRow[] foundRows = load.Tables[0].Select(ask); DataTable dt = new DataTable(); table.Columns.Add("ID", typeof(int)); table.Columns.Add("Customer Name",typeof(string)); table.Columns.Add("Contact Name", typeof(string)); table.Columns.Add("Adress", typeof(string)); table.Columns.Add("City", typeof(string)); table.Columns.Add("Postal Code", typeof(string)); table.Columns.Add("Country", typeof(string)); foreach (DataRow item in foundRows) { dt.Rows.Add(item.ItemArray); } DataSet set = new DataSet(); set.Tables.Add(dt); </code></pre> <p>When sending DataSet #2 to the function Print(), i get an error at "dtc.AsEnumerable()" with DataSet #1 everything works fine...</p> <pre><code> static void Print(DataSet load) { DataTable dtc = load.Tables[0]; List&lt;int&gt; maxlenght = Enumerable.Range(0, dtc.Columns.Count) .Select(col =&gt; dtc.AsEnumerable() .Select(row =&gt; row[col]).OfType&lt;string&gt;() .Max(val =&gt; val.Length)).ToList(); //rest prints DataTable on a grid in console } </code></pre> <p>How can this be, while both DataSets are identical from structure?</p>
 

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