public async Task <ActionResult <Project> > PatchAsync(string id, CancellationToken cancellationToken)
{
//3- 动态更新字段 利用反射
var originProject = await _lighterDbContext.Projects.FirstOrDefaultAsync(p => p.Id == id, cancellationToken);
if (originProject == null)
{
return(NotFound());
}
var properties = _lighterDbContext.Entry(originProject).Properties.ToList();
foreach (var query in HttpContext.Request.Query)
{
var property = properties.FirstOrDefault(p => p.Metadata.Name == query.Key);
if (property == null)
{
continue;
}
var currentValue = Convert.ChangeType(query.Value.First(), property.Metadata.ClrType);
_lighterDbContext.Entry(originProject).Property(query.Key).CurrentValue = currentValue;
_lighterDbContext.Entry(originProject).Property(query.Key).IsModified = true;
}
await _lighterDbContext.SaveChangesAsync();
return(originProject);
}
public async Task<IActionResult> GetAsync(string id, CancellationToken cancellationToken)
{
//// 预先加载
//var project = await _lighterDbContext.Projects.Include(p => p.Groups)
// .FirstOrDefaultAsync(p => p.Id == id, cancellationToken);
// 显式加载
var project = await _lighterDbContext.Projects.FirstOrDefaultAsync(p => p.Id == id, cancellationToken);
await _lighterDbContext.Entry(project).Collection(p => p.Groups).LoadAsync(cancellationToken);
//// 延迟加载
//project.Groups// 引用到属性时才加载
//foreach (var project in _lighterDbContext.Projects)
//{
// project.Groups// 多次查询数据库
//}
//// 一次性查询
//var projects = _lighterDbContext.Projects.ToList();
return Ok(project);
}
