C# 如何向已包含数据的数据表添加新列和数据？
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/2312966/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
How can I add a new column and data to a datatable that already contains data?
提问by Michael Kniskern
How do I add a new DataColumnto a DataTableobject that already contains data?
如何DataColumn向DataTable已包含数据的对象添加新对象？
PseudoCode
伪代码
//call SQL helper class to get initial data
DataTable dt = sql.ExecuteDataTable("sp_MyProc");
dt.Columns.Add("NewColumn", type(System.Int32));
foreach(DataRow row in dr.Rows)
{
//need to set value to NewColumn column
}
采纳答案by marc_s
Just keep going with your code - you're on the right track:
继续使用您的代码 - 您走在正确的轨道上：
//call SQL helper class to get initial data
DataTable dt = sql.ExecuteDataTable("sp_MyProc");
dt.Columns.Add("NewColumn", typeof(System.Int32));
foreach(DataRow row in dt.Rows)
{
//need to set value to NewColumn column
row["NewColumn"] = 0; // or set it to some other value
}
// possibly save your Dataset here, after setting all the new values
回答by Imir Hoxha
Should it not be foreachinstead of for!?
不应该是foreach代替吗！？
//call SQL helper class to get initial data
DataTable dt = sql.ExecuteDataTable("sp_MyProc");
dt.Columns.Add("MyRow", **typeof**(System.Int32));
foreach(DataRow dr in dt.Rows)
{
//need to set value to MyRow column
dr["MyRow"] = 0; // or set it to some other value
}
回答by Nishantha
Only you want to set default value parameter. This calling third overloading method.
只有你想设置默认值参数。这调用了第三个重载方法。
dt.Columns.Add("MyRow", type(System.Int32),0);
回答by Akxaya
Here is an alternate solution to reduce For/ForEach looping, this would reduce looping time and updates quickly :)
这是减少 For/ForEach 循环的替代解决方案，这将减少循环时间并快速更新:)
dt.Columns.Add("MyRow", typeof(System.Int32));
dt.Columns["MyRow"].Expression = "'0'";
回答by Himanshu Shukla
Try this
尝试这个
> dt.columns.Add("ColumnName", typeof(Give the type you want));
> dt.Rows[give the row no like or or any no]["Column name in which you want to add data"] = Value;
