C# 如何从gridview获取TableName?
我正在使用实体框架和我填充的网格控件C# 如何从gridview获取TableName?,c#,entity-framework,devexpress,devexpress-gridcontrol,C#,Entity Framework,Devexpress,Devexpress Gridcontrol,我正在使用实体框架和我填充的网格控件 Models.dbContext ent = new Models.dbContext(); ent.Locations.Load(); gridControl1.DataSource = ent.Locations.Local.ToBindingList(); 然后我试着得到表名,比如 DataTable dt = ((DataView)gridview1.DataSource).Table; Messagebox.Show(
Models.dbContext ent = new Models.dbContext();
ent.Locations.Load();
gridControl1.DataSource = ent.Locations.Local.ToBindingList();
然后我试着得到表名,比如
DataTable dt = ((DataView)gridview1.DataSource).Table;
Messagebox.Show(dt.TableName);
它给了我错误:无法将类型为“System.Data.Entity.Internal.ObservableBackedBindingList`1[Models.Location]”的对象强制转换为类型为“System.Data.DataView”
为什么会发生这种情况?我的代码有什么问题?您可以尝试为DataGridView创建一个扩展方法,以便将其转换为DataTable:
public static class DataGridViewExtension
{
// Method for: DataGridView to DataTable conversion
public static DataTable ToTable(this DataGridView dataGridView, bool onlyVisible=false)
{
// Identifiers used are:
int rowCount = dataGridView.Rows.Count;
var dataTable = new DataTable();
var columnTypes = new Dictionary<string, Type>();
var rowItems = new List<object>();
// Get the column names and types
columnTypes = dataGridView.ColumnTypes(onlyVisible);
// Setup the DataTable column structure
dataTable.SetupColumns(columnTypes);
// Get the rows of the DataGridView
foreach (DataGridViewRow row in dataGridView.Rows)
{
// Get the row as a list to give to the table
rowItems = row.ToList(onlyVisible);
// Give the row items to the DataTable
dataTable.Rows.Add(rowItems.ToArray());
}
// Return the data table
return dataTable;
}
}
当然,这种方法很枯燥,但如果您很匆忙,它会起作用,如果您需要这些扩展来做其他事情,它会很有用。
gridControl1.DataSource=ent.Locations.Local.ToBindingList()
您将DataSource
设置为英语,然后期望从DataSource
获取DataView
。绑定列表!=DataViewNow我看到了,但这是我第一次使用BindingList,在这种情况下如何获取TableName?您可以将TableName存储在标记
属性或TableFrom BindingList-任务不可能。将表名存储在其他地方。因此,我必须了解有关列表的更多信息。谢谢
public static class DataGridViewExtension
{
// Class for: Getting the column names with column types from a DataGridView
public static Dictionary<string, Type> ColumnTypes(this DataGridView dataGridView,
bool onlyVisible=false)
{
// Identifiers used are:
var types = new Dictionary<string, Type>();
// Go through the columns of the view
foreach (DataGridViewColumn column in dataGridView.Columns)
{
if (onlyVisible == true && column.Visible == true)
{
types[column.HeaderText] = column.ValueType;
}
else if (!onlyVisible)
{
types[Column.HeaderText] = column.ValueType;
}
}
// Return the results
return types;
}
}
public static class DataGridViewRowExtension
{
// Method for: Returning the cells of a row as a List<object>
public static List<object> ToList(this DataGridViewRow dataGridViewRow,
bool onlyVisible= false)
{
// Identifiers used are:
var objectList = new List<object>();
// Go through the row and add the items to the list
foreach (DataGridViewCell cell in dataGridViewRow.Cells)
{
if (onlyVisible == true && cell.Visible == true)
{
objectList.Add(cell.Value);
}
else if (!onlyVisible)
{
objectList.Add(cell.Value);
}
}
// Return the list
return objectList;
}
}
public static class DataTableExtension
{
// Method for: Setting up the column structure of a data table using a dictionary holding column name with data type
public static void SetupColumns(this DataTable dataTable,
Dictionary<string, Type> columns)
{
// Identifiers used are:
int columnCount = columns.Count;
// Set up the structure
foreach (KeyValuePair<string, Type> column in columns)
{
dataTable.Columns.Add(column.Key, column.Value);
}
}
}
string tableName = dataGridView.ToTable().TableName;