Like Extension Linq / SQL
LikeExtension Class
Tested in .NET 5
public static class LikeExtension {
private static string ColumnDataBase<TEntity, TKey>(IModel model, Expression<Func<TEntity, TKey>> predicate) where TEntity : class {
ITable table = model
.GetRelationalModel()
.Tables
.First(f => f
.EntityTypeMappings
.First()
.EntityType == model
.FindEntityType(predicate
.Parameters
.First()
.Type
));
string column = (predicate.Body as MemberExpression).Member.Name;
string columnDataBase = table.Columns.First(f => f.PropertyMappings.Count(f2 => f2.Property.Name == column) > 0).Name;
return columnDataBase;
}
public static IQueryable<TEntity> Like<TEntity, TKey>(this DbContext context, Expression<Func<TEntity, TKey>> predicate, string text) where TEntity : class {
string columnDataBase = ColumnDataBase(context.Model, predicate);
return context.Set<TEntity>().FromSqlRaw(context.Set<TEntity>().ToQueryString() + " WHERE [" + columnDataBase + "] LIKE {0}", text);
}
public static async Task<IEnumerable<TEntity>> LikeAsync<TEntity, TKey>(this DbContext context, Expression<Func<TEntity, TKey>> predicate, string text, CancellationToken cancellationToken) where TEntity : class {
string columnDataBase = ColumnDataBase(context.Model, predicate);
return await context.Set<TEntity>().FromSqlRaw(context.Set<TEntity>().ToQueryString() + " WHERE [" + columnDataBase + "] LIKE {0}", text).ToListAsync(cancellationToken);
}
public static async Task<IEnumerable<TEntity>> LikeAsync<TEntity, TKey>(this IQueryable<TEntity> query, Expression<Func<TEntity, TKey>> predicate, string text, CancellationToken cancellationToken) where TEntity : class {
DbSet<TEntity> entities = query as DbSet<TEntity>;
string columnDataBase = ColumnDataBase(entities.EntityType.Model, predicate);
return await entities.FromSqlRaw(query.ToQueryString() + " WHERE [" + columnDataBase + "] LIKE {0}", text).ToListAsync(cancellationToken);
}
public static IQueryable<TEntity> Like<TEntity, TKey>(this IQueryable<TEntity> query, Expression<Func<TEntity, TKey>> predicate, string text) where TEntity : class {
DbSet<TEntity> entities = query as DbSet<TEntity>;
string columnDataBase = ColumnDataBase(entities.EntityType.Model, predicate);
return entities.FromSqlRaw(query.ToQueryString() + " WHERE [" + columnDataBase + "] LIKE {0}", text);
}
}
Repository
public async Task<IEnumerable<TEntity>> LikeAsync<TKey>(Expression<Func<TEntity, TKey>> predicate, string text, CancellationToken cancellationToken) {
return await context.LikeAsync(predicate, text, cancellationToken);
}
public IQueryable<TEntity> Like<TKey>(Expression<Func<TEntity, TKey>> predicate, string text) {
return context.Like(predicate, text);
}
Use
IQueryable<CountryEntity> result = countryRepository
.Like(k => k.Name, "%Bra[sz]il%") /*Use Sync*/
.Where(w => w.DateRegister < DateTime.Now) /*Example*/
.Take(10); /*Example*/
Or
IEnumerable<CountryEntity> result = await countryRepository
.LikeAsync(k => k.Name, "%Bra[sz]il%", cancellationToken); /*Use Async*/
Or
IQueryable<CountryEntity> result = context.Countries
.Like(k => k.Name, "%Bra[sz]il%")
.Where(w => w.Name != null); /*Example*/
Or
List<CountryEntity> result2 = await context.Countries
.Like(k => k.Name, "%Bra[sz]il%")
.Where(w => w.Name != null) /*Example*/
.ToListAsync(); /*Use Async*/
Or
IEnumerable<CountryEntity> result3 = await context.Countries
.Where(w => w.Name != null)
.LikeAsync(k => k.Name, "%Bra[sz]il%", cancellationToken); /*Use Async*/
