DataTable中的LINQ加入许多列 [英] DataTable Linq join many columns
问题描述
我有Linq的麻烦加入。我想加入2表,这是他们与n列相同的结构。我的问题是我不知道这些列的名字,所以,我怎么可以重写那些在选择新的
表1:在这里,我有身份证一些参数,名字和姓氏。注释,属性,其余都为空
ID名称姓氏评论...属性
是什么ABC ...
你好,SDE......
3萝拉
1日
4美姬
... ... ... ...
表2:这里是同样喜欢表1,但它在注释,属性和一些参数休息。
ID名称姓氏评论...属性
是什么ABC...
你好SDE......
1日的hi
4三木OKK
3萝拉哟,LL
结果:我想加入表这样的
ID名称姓氏评论...属性
是什么ABC...
你好,SDE......
3萝拉哟,LL
1日的hi
4三木OKK
... ... ... ... ... ...
我的代码是:
VAR结果=从TB1在table1.AsEnumerable()
在tabl2.AsEnumerable加入TB2()新的
{
名称= tb1.Field<
;弦乐>(姓名),
姓氏= tb1.Field<弦乐>(姓氏),
}等于新的
{
名称= tb2.Field<弦乐>(姓名),
姓氏= tb2.Field<弦乐>(姓氏),
}
到来自TB3在grp1.DefaultIfEmpty()
GRP1
选择新的
{
ID = tb1.Field<弦乐>(ID),
名称= tb1.Field<弦乐>(姓名),
姓氏= tb1.Field<弦乐>(姓 ),
注释= TB3!= NULL? tb3.Field<串GT;(注释):空,
属性= TB3!= NULL? tb3.Field<串GT(属性):空,
...
//这里应该是下一个字段名字,但不知道如何把有
};
我试着用这个代码,但我的编译器只是挂出,不知道为什么。
的for(int i = 2; I< table1.Rows.Count;我++)
{
的foreach(在table2.Rows的DataRow DR)
{
如果((table1.Rows [I] [名称]。的ToString()==博士[名称]的ToString())及和放大器; table1.Rows [I] [姓氏]的ToString()==博士[姓氏]的ToString())
{
table1.Rows。 RemoveAt移除(ⅰ);
table1.ImportRow(DR);
}
}
}
dataGridView1.DataSource = table1的;
对于表1各ROW1,如果有一个匹配ROW2表2中,使用ROW2。否则,使用ROW1
VAR newtable的= table1.Clone();
的foreach(在table1.Rows的DataRow ROW1)//跳过第2,使用table1.Rows.Cast< DataRow的方式>()跳过(2)
{
无功行=表2 .Rows.Cast< DataRow的>()FirstOrDefault(ROW2 =方式>
ROW1 [名称]的ToString()== ROW2 [名称]的ToString()及。和放大器;
ROW1 [姓氏]。的ToString()== ROW2 [姓氏]。的ToString())? ROW1;
newTable.ImportRow(行);
}
dataGridView1.DataSource = newtable的;
I have a trouble with Linq Join. I want to join 2 tables, which they have same structure with n-columns. My problem is i don't know the names of those columns, so how can i rewrite those in select new?
Table 1: Here I have some parameters in ID, Name and LastName. Comment, Attribute and the rest are null
ID Name LastName Comment Attribute ...
"what" "ABC" ...
"hello" "SDE" ...
3 lola
1 de
4 miki
... ... ... ...
Table 2: Here is the same like Table 1 but it has some parameters in Comment, Attribute and the Rest.
ID Name LastName Comment Attribute ...
"what" "ABC" ...
"hello" "SDE" ...
1 de "hi"
4 miki "OKK"
3 lola "yo" "LL"
Result: I would like to have joined Table like this
ID Name LastName Comment Attribute ...
"what" "ABC" ...
"hello" "SDE" ...
3 lola "yo" "LL"
1 de "hi"
4 miki "OKK"
... ... ... ... ... ...
My Code would be:
var Result= from tb1 in table1.AsEnumerable()
join tb2 in tabl2.AsEnumerable()
on new
{
Name = tb1.Field<String>("Name"),
LastName = tb1.Field<String>("LastName"),
} equals new
{
Name=tb2.Field<String>("Name"),
LastName=tb2.Field<String>("LastName"),
}
into grp1
from tb3 in grp1.DefaultIfEmpty()
select new
{
ID = tb1.Field<String>("ID"),
Name = tb1.Field<String>("Name") ,
LastName = tb1.Field<String>("LastName"),
Comment = tb3!= null ? tb3.Field<String>("Comment") : null,
Attribute= tb3!= null ? tb3.Field<String>("Attribute") : null,
...
// Here should be next Columns Name but don't know how to put there
};
I tried with this code but my compiler just hanged out, dont know why
for (int i = 2; i < table1.Rows.Count; i++)
{
foreach (DataRow dr in table2.Rows)
{
if ((table1.Rows[i]["Name"].ToString() == dr["Name"].ToString())&&table1.Rows[i]["LastName"].ToString() == dr["LastName"].ToString())
{
table1.Rows.RemoveAt(i);
table1.ImportRow(dr);
}
}
}
dataGridView1.DataSource = table1;
For each row1 in table1, if there is a matching row2 in table2, use row2. Otherwise, use row1.
var newTable = table1.Clone();
foreach (DataRow row1 in table1.Rows) // To skip the first 2, use table1.Rows.Cast<DataRow>().Skip(2)
{
var row = table2.Rows.Cast<DataRow>().FirstOrDefault(row2 =>
row1["Name"].ToString() == row2["Name"].ToString() &&
row1["LastName"].ToString() == row2["LastName"].ToString()) ?? row1;
newTable.ImportRow(row);
}
dataGridView1.DataSource = newTable;
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