DataTable的一些特殊用法：Select
/**//*
* 補(bǔ)充一下，還可以利用DataView來(lái)達(dá)到檢索的目的。
*/
DataTable dataSource = new DataTable();
DataView dv = dataSource.DefaultView;
dv.RowFilter = "columnA = 'abc'";
//1.過(guò)濾后直接獲取DataTable
DataTable newTable1 = dv.ToTable();
//2.設(shè)置新DataTable的TableName
DataTable newTable2 = dv.ToTable("NewTableName");
//3.設(shè)置新表是否過(guò)濾重復(fù)項(xiàng),擁有的列的列名以及出現(xiàn)的順序
//即可以設(shè)置新表的字段。但是字段名肯定是老表dataSource中擁有的。
DataTable newTable3 =
dv.ToTable(true, new string[] 
{ "columnA,columnF,columnC" });
//4.綜合了2.3兩點(diǎn)。
DataTable newTable4 =
dv.ToTable("NewTableName", true, new string[] { "columnA,columnF,columnC" });
簡(jiǎn)化，利用 DataView過(guò)濾
DataView dv = this.dtPerson.DefaultView; //設(shè)置一個(gè)視圖過(guò)濾
dv.RowFilter = "employee_dept_id = " + departId;
this.lstSource.DataSource = dv;
this.lstSource.DisplayMember = "employee_name";
this.lstSource.ValueMember = "id";
this.dvPendingNode.RowFilter = "(node_end_time is null or node_end_time > '2009-6-10 17:55:13')";
this.dvPendingNode.RowFilter += "and degree_name in ('', '進(jìn)行', '暫停', '擱置') ";
1. 我在一個(gè)winform程序里用DataView的RowFilter篩選時(shí)用兩個(gè)下劃線代表兩個(gè)字符，但是怎么篩選不出來(lái)的?
http://topic.csdn.net/t/20040814/04/3273316.html
Q:
我在一個(gè)winform程序里用DataView的RowFilter篩選時(shí)用兩個(gè)下劃線代表兩個(gè)個(gè)字符，如：
dv.RowFilter="PID LIKE '"+str+"-__"，這樣的篩選語(yǔ)句在SQL企業(yè)管理器里執(zhí)行是能正確篩選到記錄的，但是為什么在這里就一個(gè)都篩選不出來(lái)？是不是這里要用別的符號(hào)來(lái)代表一個(gè)字符啊。
A:
"_" is probably very sql server specific, classes in System.Data is supposed to be DBMS independent, you can try to use
ABC LIKE 'abc*' AND LEN(ABC)=5
2. ListBox 多項(xiàng)選擇（DataRowView）
for (int i = 0; i < this.lstSource.SelectedItems.Count; i++)
{
DataRowView row = this.lstSource.SelectedItems[i] as DataRowView;
int id = Int32.Parse(row["id"].ToString());
string employee = String.Format("{0}<{1}>", row["employee_name"], row["dept_name"]);
//數(shù)據(jù)填充
if (!this.idList.Contains(id))
{
this.idList.Add(id);
this.valueList.Add(employee);
}
System.Windows.Forms.ListBox.SelectedIndexCollection indexes = this.lstTarget.SelectedIndices;
for (int i = indexes.Count - 1; i >= 0; i--)
{
this.idList.RemoveAt(indexes[i]);
this.valueList.RemoveAt(indexes[i]);
}
posted on 2010-04-22 12:35
黃小二 閱讀(1661)
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