/// <summary>
/// 获取指定类型对应的数据源。
/// </summary>
/// <param name="entityType">实体类型。</param>
/// <param name="throwIfNotFound">未发现元数据时是否抛异常。</param>
public DapperDataSource GetDataSource(Type entityType, bool throwIfNotFound = true)
{
return(_mappedDataSources.GetOrAdd(entityType, et =>
{
DapperMetadata metadata = GetMetadata(et, throwIfNotFound);
return GetDataSource(metadata?.ReadingConnectionName, metadata?.WritingConnectionName);
}));
}
/// <summary>
/// 构造函数
/// </summary>
/// <param name="dapperContext">dapper上下文</param>
/// <param name="loggerFactory">日志组件</param>
public DapperRepository(DapperContext dapperContext, ILoggerFactory loggerFactory = null)
{
Guard.ArgumentNotNull(dapperContext, nameof(dapperContext));
Context = dapperContext;
_metadata = dapperContext.Runtime.GetMetadata(typeof(T));
_loggerLazy = new Lazy <ILogger>(() => loggerFactory?.CreateLogger <DapperRepository <T> >() ?? NullLogger <DapperRepository <T> > .Instance);
}
/// <summary>
/// 根据实体类型获取 Dapper 配置的元数据。
/// </summary>
/// <param name="entityType">实体类型。</param>
/// <param name="throwIfNotFound">未发现元数据时是否抛异常</param>
/// <returns></returns>
public DapperMetadata GetMetadata(Type entityType, bool throwIfNotFound = true)
{
if (_metadataSet.TryGetValue(entityType, out DapperMetadata value))
{
return(value);
}
var convention = _options.Value.GetModelConvention();
var item = convention.TypeConventions.FirstOrDefault(x => x.Filter(entityType));
if (item == null && throwIfNotFound)
{
throw new InvalidOperationException(
$"找不到类型 {entityType.Name} 的元数据提供程序， 请确保已经通过 {typeof(DapperMetadataProvider<>).Name} 或者{typeof(TypeConvention).Name}实现了元数据提供程序。");
}
value = new DapperMetadata(entityType, item, convention);
_metadataSet.TryAdd(entityType, value);
return(value);
}
/// <summary>
/// 生成插入的SQL语句
/// </summary>
/// <param name="entityType">实体类型</param>
/// <param name="runtime">Dapper运行时</param>
/// <param name="metadata">Dapper元数据</param>
/// <returns></returns>
private static string GenerateInsertSql(Type entityType, DapperRuntime runtime, DapperMetadata metadata)
{
var fields = metadata.Fields.Where(f => !f.Ignore && !f.AutoGeneration).OrderBy(x => x.Field.Name).ToArray();
string columns = fields.Select(k => runtime.DelimitIdentifier(entityType, k.Name)).ToArrayString(", ");
string parameters = fields.Select(k => $"{runtime.DelimitParameter(entityType, k.Field.Name)}").ToArrayString(", ");
StringBuilder sqlBuilder = new StringBuilder();
sqlBuilder.Append("INSERT INTO ");
sqlBuilder.Append($"{runtime.DelimitIdentifier(entityType, metadata.TableName)} ");
sqlBuilder.Append($"({columns}) ");
sqlBuilder.Append(" VALUES ");
sqlBuilder.Append($"({parameters})");
return(sqlBuilder.ToString());
}
/// <summary>
/// 使用界定符包围T-SQL中的参数字符串。
/// </summary>
/// <param name="entityType">实体类型</param>
/// <param name="runtime">Dapper运行时</param>
/// <param name="metadata">Dapper元数据</param>
/// <returns></returns>
private static string KeyDelimitSegment(Type entityType, DapperRuntime runtime, DapperMetadata metadata)
{
return(metadata.Fields.Where(f => f.IsKey).Select(k => $"{runtime.DelimitIdentifier(entityType, k.Name)} = {runtime.DelimitParameter(entityType, k.Field.Name)}").ToArrayString(" AND "));
}
/// <summary>
/// 生成查询的SQL语句
/// </summary>
/// <param name="entityType">实体类型</param>
/// <param name="runtime">Dapper运行时</param>
/// <param name="metadata">Dapper元数据</param>
/// <returns></returns>
private static string GenerateSelectSql(Type entityType, DapperRuntime runtime, DapperMetadata metadata)
{
string columnsSetSeg =
metadata.Fields.Where(f => !f.Ignore).OrderBy(x => x.Field.Name)
.Select(k => runtime.DelimitIdentifier(entityType, k.Name)).ToArrayString(", ");
StringBuilder sqlBuilder = new StringBuilder();
sqlBuilder.Append("SELECT ");
sqlBuilder.Append(columnsSetSeg);
sqlBuilder.Append(" FROM ");
sqlBuilder.Append($"{runtime.DelimitIdentifier(entityType, metadata.TableName)}");
return(sqlBuilder.ToString());
}
/// <summary>
/// 生成删除的SQL语句
/// </summary>
/// <param name="entityType">实体类型</param>
/// <param name="runtime">Dapper运行时</param>
/// <param name="metadata">Dapper元数据</param>
/// <returns></returns>
private static string GenerateDeleteSql(Type entityType, DapperRuntime runtime, DapperMetadata metadata)
{
string whereSeg = KeyDelimitSegment(entityType, runtime, metadata);
StringBuilder sqlBuilder = new StringBuilder();
sqlBuilder.Append("DELETE FROM ");
sqlBuilder.Append($"{runtime.DelimitIdentifier(entityType, metadata.TableName)} ");
if (!string.IsNullOrWhiteSpace(whereSeg))
{
sqlBuilder.Append(" WHERE ");
sqlBuilder.Append(whereSeg);
}
return(sqlBuilder.ToString());
}
/// <summary>
/// 生成更新的SQL语句
/// </summary>
/// <param name="entityType">实体类型</param>
/// <param name="runtime">Dapper运行时</param>
/// <param name="metadata">Dapper元数据</param>
/// <returns></returns>
private static string GenerateUpdateSql(Type entityType, DapperRuntime runtime, DapperMetadata metadata)
{
var fields = metadata.Fields.Where(f => !f.IsKey && !f.AutoGeneration && !f.Ignore).OrderBy(x => x.Field.Name).ToArray();
string columnsSetSeg = fields.Select(k =>
$"{runtime.DelimitIdentifier(entityType, k.Name)} = {runtime.DelimitParameter(entityType, k.Field.Name)}").ToArrayString(", ");
string whereSeg = KeyDelimitSegment(entityType, runtime, metadata);
StringBuilder sqlBuilder = new StringBuilder();
sqlBuilder.Append("UPDATE ");
sqlBuilder.Append($"{runtime.DelimitIdentifier(entityType, metadata.TableName)} ");
sqlBuilder.Append("SET ");
sqlBuilder.Append(columnsSetSeg);
if (!string.IsNullOrWhiteSpace(whereSeg))
{
sqlBuilder.Append(" WHERE ");
sqlBuilder.Append(whereSeg);
}
return(sqlBuilder.ToString());
}
