blazor-devexpress-dot-blazor-dot-dxgridcolumn-2d3ed7b3.md
Specifies a template used to display the column header’s caption.
Namespace : DevExpress.Blazor
Assembly : DevExpress.Blazor.v25.2.dll
NuGet Package : DevExpress.Blazor
[Parameter]
public RenderFragment<GridColumnHeaderCaptionTemplateContext> HeaderCaptionTemplate { get; set; }
| Type | Description |
|---|---|
| RenderFragment<GridColumnHeaderCaptionTemplateContext> |
The template for the column header’s caption.
|
The HeaderCaptionTemplate allows you to customize captions of individual column headers. To define a common template for all header captions in the Grid, use the DxGrid.ColumnHeaderCaptionTemplate.
The HeaderCaptionTemplate accepts a GridColumnHeaderCaptionTemplateContext object as the context parameter. You can use the parameter’s members to get the current Caption, and the Column or DataColumn object. You can also access the Grid object and use its members to obtain additional information about the Grid.
The following example shows a tooltip when a user hovers the mouse pointer over the Details column caption. The example also specifies the CellDisplayTemplate to display the More Info… links in column cells.
@using Microsoft.EntityFrameworkCore
@inject IDbContextFactory<NorthwindContext> NorthwindContextFactory
@implements IDisposable
<DxGrid Data="@Data">
<Columns>
<DxGridDataColumn FieldName="FirstName" />
<DxGridDataColumn FieldName="LastName" />
<DxGridDataColumn FieldName="Title" />
<DxGridDataColumn FieldName="BirthDate" />
<DxGridDataColumn FieldName="HireDate" />
<DxGridDataColumn FieldName="EmployeeId" Caption="Details" AllowSort="false">
<HeaderCaptionTemplate>
<span title="Click a link below to show more information about an employee">Details</span>
</HeaderCaptionTemplate>
<CellDisplayTemplate>
<a class="d-block text-left" href="javascript:;" @onclick="() => ShowDetails(context)">More Info...</a>
</CellDisplayTemplate>
</DxGridDataColumn>
</Columns>
</DxGrid>
<DxPopup @bind-Visible="@PopupVisible"
HeaderText="@PopupHeaderText"
HorizontalAlignment="HorizontalAlignment.Center"
VerticalAlignment="VerticalAlignment.Center">
@PopupContent
</DxPopup>
@code {
IEnumerable<Employee> Data { get; set; }
NorthwindContext Northwind { get; set; }
Employee CurrentEmployee { get; set; }
protected override void OnInitialized() {
Northwind = NorthwindContextFactory.CreateDbContext();
Data = Northwind.Employees
.ToList();
}
bool PopupVisible {
get { return CurrentEmployee != null; }
set { if (!value) CurrentEmployee = null; }
}
string PopupHeaderText {
get { return CurrentEmployee != null ? CurrentEmployee.FirstName + " " + CurrentEmployee.LastName : ""; }
}
string PopupContent {
get { return CurrentEmployee != null ? CurrentEmployee.Notes : ""; }
}
public void ShowDetails(GridDataColumnCellDisplayTemplateContext context) {
CurrentEmployee = Data.Where(e => e.EmployeeId == (int)context.Value).FirstOrDefault();
}
public void Dispose() {
Northwind?.Dispose();
}
}
using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
namespace Grid.Northwind {
public partial class Employee {
public int EmployeeId { get; set; }
[Required]
public string LastName { get; set; }
[Required]
public string FirstName { get; set; }
[Required]
public string Title { get; set; }
public string TitleOfCourtesy { get; set; }
public Nullable BirthDate { get; set; }
[Required]
[Range(typeof(DateTime), "1/1/2000", "1/1/2020",
ErrorMessage = "HireDate must be between {1:d} and {2:d}")]
public Nullable HireDate { get; set; }
public string Address { get; set; }
public string City { get; set; }
public string Region { get; set; }
public string PostalCode { get; set; }
public string Country { get; set; }
public string HomePhone { get; set; }
public string Extension { get; set; }
public byte[] Photo { get; set; }
public string Notes { get; set; }
public Nullable<int> ReportsTo { get; set; }
public string PhotoPath { get; set; }
public virtual ICollection<Order> Orders { get; set; }
public string Text => $"{FirstName} {LastName} ({Title})";
public string ImageFileName => $"Employees/{EmployeeId}.jpg";
}
}
using Microsoft.EntityFrameworkCore;
#nullable disable
namespace Grid.Northwind {
public partial class NorthwindContext : DbContext {
public NorthwindContext(DbContextOptions<NorthwindContext> options)
: base(options) {
}
// ...
public virtual DbSet<Employee> Employees { get; set; }
// ...
protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder) {
if(!optionsBuilder.IsConfigured) {
optionsBuilder.UseSqlServer("Server=.\\sqlexpress;Database=Northwind;Integrated Security=true");
}
}
// ...
protected override void OnModelCreating(ModelBuilder modelBuilder) {
// ...
modelBuilder.Entity<Employee>(entity => {
entity.HasIndex(e => e.EmployeeId, "EmployeeId");
entity.HasIndex(e => e.LastName, "LastName");
entity.HasIndex(e => e.FirstName, "FirstName");
entity.HasIndex(e => e.Title, "Title");
entity.HasIndex(e => e.BirthDate, "BirthDate");
entity.HasIndex(e => e.HireDate, "HireDate");
entity.HasIndex(e => e.Notes, "Notes");
});
OnModelCreatingPartial(modelBuilder);
}
partial void OnModelCreatingPartial(ModelBuilder modelBuilder);
}
}
using Microsoft.EntityFrameworkCore;
// ...
builder.Services.AddDbContextFactory<NorthwindContext>((sp, options) => {
var env = sp.GetRequiredService<IWebHostEnvironment>();
var dbPath = Path.Combine(env.ContentRootPath, "Northwind-5e44b51f.mdf");
options.UseSqlServer("Server=(localdb)\\MSSQLLocalDB;Integrated Security=true;AttachDbFileName=" + dbPath);
});
Run Demo: Grid - Column Templates
For additional information about templates in the Grid component, refer to the following topic: Templates in Blazor Grid.
See Also