Bind to Data Source

• Apr 09, 2021
• 6 minutes to read

DevExpress data controls support ADO.NET, Entity Framework, eXpress Persistent Objects, and other data access technologies. You can also bind a data control to an IList, IBindingList, or ITypedList object. See the following topics for more information: Traditional Data Binding Methods and Data Binding Common Concepts.

This topic explains mappings between data fields in the main data source and task properties. The GanttControl also supports additional data sources that allow you to store information about dependencies (of multiple types) and split tasks. See the following topics for more information: Task Dependencies and Split a Partially Completed Task.

Main Data Source

The DataSource property specifies the control’s main data source. The tables below contain data fields that the data source should include to display a project such as hierarchy, dates, and dependencies.

Note

Make sure that you specified all required mappings. Otherwise, specific functionality may not be available.

Task List Area Mappings

The TreeListMappings property specifies data fields that contain parent-child relationships between tasks.

Field	Description	Default Field Name	Property that Specifies the Field Name	Data Type
Key	A data field that contains a task’s unique identifier.	“ID”	KeyFieldName	Object
Parent’s Key	A data field that contains a parent task’s unique identifier. Use this data field to specify hierarchy.	“ParentID”	ParentFieldName	Object

Chart Area Mappings

The ChartMappings property specifies data fields that contain information about bars in the chart area.

Field	Description	Default Field Name	Property that Specifies the Field Name	Data Type
Start Date	A data field that contains a task’s start date.	“StartDate”	StartDateFieldName	DateTime
Finish Date	A data field that contains a task’s finish date. You can use either Finish Date or Duration.	“FinishDate”	FinishDateFieldName	DateTime
Duration	A data field that contains a task’s duration. You can use either Duration or Finish Date.	Empty	DurationFieldName	TimeSpan
Text	A data field that contains a caption displayed next to a task in the chart. Note that this field does not have a default name. You must specify it to display task captions in the chart.	Empty	TextFieldName	String
Tooltip Text	A data field that contains a task’s caption in tooltips. Note that this field does not have a default name. You must specify it to display task captions in tooltips.	Empty	InteractionTooltipTextFieldName	String
Progress	A data field that contains a task’s completion percentage.	“Progress”	ProgressFieldName	Single

Baselines

Baselines allow you to display a task’s planned start and finish dates, and duration. Note that baselines are only displayed if the ShowBaselines option is enabled. See the following topic for more information: Task Baselines.

Field	Description	Default Field Name	Property that Specifies the Field Name	Data Type
Baseline Start Date	A data field that contains a baseline’s start date.	“BaselineStartDate”	BaselineStartDateFieldName	DateTime
Baseline Finish Date	A data field that contains a baseline’s finish date. You can use either Baseline Finish Date or Baseline Duration.	“BaselineFinishDate”	BaselineFinishDateFieldName	DateTime
Baseline Duration	A data field that contains a baseline’s duration. You can use either Baseline Duration or Baseline Finish Date. Note that this field does not have a default name. You must specify it to specify baseline durations.	Empty	BaselineDurationFieldName	TimeSpan

Dependencies

The main data source supports the finish-to-start dependency type only. To specify other dependency types, you should use an additional data source. You also cannot specify a time lag between dependent tasks if you use the main data source to store dependencies. See the following topic for more information: Task Dependencies.

Field	Description	Default Field Name	Property that Specifies the Field Name	Data Type
Predecessors	A data field that contains a task’s predecessors. The field should contain predecessor keys separated by a space, comma, or semicolon (‘ ‘, ‘,’ ‘;’).	“Predecessors”	PredecessorsFieldName	String, IList

Task Constraints

Task constraints allow you to limit a task’s start or finish date to a specific date or date range.

Field	Description	Default Field Name	Property that Specifies the Field Name	Data Type
Constraint Type	A data field that contains the constraint types (As Soon As Possible, Start No Earlier Than, and so on).	“ConstraintType”	ConstraintTypeFieldName	ConstraintType, Int32
Limit Date	A data field that contains the limit date.	“ConstraintDate”	ConstraintDateFieldName	DateTime

See the following topic for more information: Task Constraints.

Example

The code below shows how to initialize tree list and chart mappings.

C#

ganttControl1.TreeListMappings.KeyFieldName = "ID";
ganttControl1.TreeListMappings.ParentFieldName = "ParentID";
ganttControl1.ChartMappings.TextFieldName = "Text";
ganttControl1.ChartMappings.StartDateFieldName = "StartDate";
ganttControl1.ChartMappings.FinishDateFieldName = "FinishDate";
ganttControl1.ChartMappings.BaselineStartDateFieldName = "BaselineStartDate";
ganttControl1.ChartMappings.BaselineFinishDateFieldName = "BaselineFinishDate";
ganttControl1.OptionsView.ShowBaselines = true;
ganttControl1.ChartMappings.PredecessorsFieldName = "Predecessors";
ganttControl1.DataSource = GetTasks();

DataTable GetTasks() {
    DataTable table = new DataTable();
    DataColumn id = new DataColumn("ID", typeof(int));
    DataColumn parentId = new DataColumn("ParentID", typeof(int));
    DataColumn text = new DataColumn("Text", typeof(string));
    DataColumn start = new DataColumn("StartDate", typeof(DateTime));
    DataColumn finish = new DataColumn("FinishDate", typeof(DateTime));
    DataColumn startBaseline = new DataColumn("BaselineStartDate", typeof(DateTime));
    DataColumn finishBaseline = new DataColumn("BaselineFinishDate", typeof(DateTime));
    DataColumn predecessors = new DataColumn("Predecessors", typeof(string));
    table.Columns.AddRange(new DataColumn[] { id, parentId, text, start, finish, startBaseline, finishBaseline, predecessors });
    table.Rows.Add(new object[] { 1, 0, "Task 1", DateTime.Now, DateTime.Now.AddDays(1), DateTime.Now, DateTime.Now.AddDays(1.5), null });
    table.Rows.Add(new object[] { 2, 0, "Task 2", DateTime.Now.AddDays(1), DateTime.Now.AddDays(2), DateTime.Now.AddDays(1), DateTime.Now.AddDays(1.5), 1 });
    table.Rows.Add(new object[] { 3, 0, "Task 3", DateTime.Now.AddDays(2), DateTime.Now.AddDays(3), DateTime.Now.AddDays(2), DateTime.Now.AddDays(3), "1, 2" });
    return table;
}

VB.NET

ganttControl1.TreeListMappings.KeyFieldName = "ID"
ganttControl1.TreeListMappings.ParentFieldName = "ParentID"
ganttControl1.ChartMappings.TextFieldName = "Text"
ganttControl1.ChartMappings.StartDateFieldName = "StartDate"
ganttControl1.ChartMappings.FinishDateFieldName = "FinishDate"
ganttControl1.ChartMappings.BaselineStartDateFieldName = "BaselineStartDate"
ganttControl1.ChartMappings.BaselineFinishDateFieldName = "BaselineFinishDate"
ganttControl1.OptionsView.ShowBaselines = True
ganttControl1.ChartMappings.PredecessorsFieldName = "Predecessors"
ganttControl1.DataSource = GetTasks()

Private Function GetTasks() As DataTable
    Dim table As New DataTable()
    Dim id As New DataColumn("ID", GetType(Integer))
    Dim parentId As New DataColumn("ParentID", GetType(Integer))
    Dim taskText As New DataColumn("Text", GetType(String))
    Dim start As New DataColumn("StartDate", GetType(DateTime))
    Dim finish As New DataColumn("FinishDate", GetType(DateTime))
    Dim startBaseline As New DataColumn("BaselineStartDate", GetType(DateTime))
    Dim finishBaseline As New DataColumn("BaselineFinishDate", GetType(DateTime))
    Dim predecessors As New DataColumn("Predecessors", GetType(String))
    table.Columns.AddRange(New DataColumn() {id, parentId, taskText, start, finish, startBaseline, finishBaseline, predecessors})
    table.Rows.Add(New Object() { 1, 0, "Task 1", DateTime.Now, DateTime.Now.AddDays(1), DateTime.Now, DateTime.Now.AddDays(1.5), Nothing })
    table.Rows.Add(New Object() { 2, 0, "Task 2", DateTime.Now.AddDays(1), DateTime.Now.AddDays(2), DateTime.Now.AddDays(1), DateTime.Now.AddDays(1.5), 1 })
    table.Rows.Add(New Object() { 3, 0, "Task 3", DateTime.Now.AddDays(2), DateTime.Now.AddDays(3), DateTime.Now.AddDays(2), DateTime.Now.AddDays(3), "1, 2" })
    Return table
End Function

Tip

Run the Code Examples - Data-binding modes - Map data source fields to task and node properties module in the XtraGantt GanttDemo for another example. Click Run In Visual Studio for source codes.