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#if EXTRA
/* 2021.08.03 */
using Apewer;
using Apewer.Source;
using System;
using System.Collections.Generic;
using System.Data;
using System.Data.SQLite;
using System.Text;
using System.Data.Common;
//using Mono.Data.Sqlite;
namespace Apewer.Source
{
/// <summary>用于快速连接 SQLite 数据库的辅助。</summary>
public class Sqlite : IDatabase, IOrm, IDisposable
{
#region 变量定义。
private SQLiteConnection _db = null;
private Timeout _timeout = new Timeout();
private string _connstring = "";
private string _path = "";
private string _pass = "";
private byte[] _passdata = BinaryUtility.EmptyBytes;
#endregion
#region this
private void VarInit(string path, Timeout timeout, string pass, byte[] passData)
{
_path = (path == null) ? "" : path;
_passdata = (passData == null) ? BinaryUtility.EmptyBytes : passData;
_pass = (pass == null) ? "" : pass;
_timeout = timeout;
}
/// <summary>连接内存。</summary>
public Sqlite() => VarInit(Memory, new Timeout(), null, null);
/// <summary>连接指定文件。</summary>
public Sqlite(string path) => VarInit(path, new Timeout(), null, null);
/// <summary>连接指定文件。</summary>
private Sqlite(string path, byte[] passData) => VarInit(path, new Timeout(), null, passData);
/// <summary>连接指定文件。</summary>
public Sqlite(string path, string pass) => VarInit(path, new Timeout(), pass, null);
/// <summary>连接指定文件。</summary>
public Sqlite(string path, Timeout timeout) => VarInit(path, timeout, null, null);
/// <summary>连接指定文件。</summary>
private Sqlite(string path, Timeout timeout, byte[] pass) => VarInit(path, timeout, null, pass);
/// <summary>连接指定文件。</summary>
public Sqlite(string path, Timeout timeout, string pass) => VarInit(path, timeout, pass, null);
#endregion
#region 日志。
/// <summary>获取或设置日志记录。</summary>
public Logger Logger { get; set; }
private void LogError(string action, Exception ex, string addtion)
{
var logger = Logger;
if (logger != null) logger.Error(this, "SQLite", action, ex.GetType().FullName, ex.Message, addtion);
}
private void LogError(string action, string message)
{
var logger = Logger;
if (logger != null) logger.Error(this, "SQLite", action, message);
}
#endregion
#region 实现接口。
/// <summary>数据库是否已经连接。</summary>
public bool Online { get => _db != null && _db.State == ConnectionState.Open; }
/// <summary>连接数据库,若未连接则尝试连接。</summary>
/// <returns>是否已连接。</returns>
public bool Connect()
{
if (_db == null)
{
_db = new SQLiteConnection();
_db.ConnectionString = ConnectionString;
//if (string.IsNullOrEmpty(_connstring) && string.IsNullOrEmpty(_pass) && (_passdata.Length > 0))
//{
// _db.SetPassword(_pass);
//}
}
else
{
if (_db.State == ConnectionState.Open) return true;
}
try
{
_db.Open();
switch (_db.State)
{
case ConnectionState.Open: return true;
default: return false;
}
}
catch (Exception ex)
{
LogError("Connection", ex, _db.ConnectionString);
Close();
return false;
}
}
/// <summary>关闭连接,并释放对象所占用的系统资源。</summary>
public void Close()
{
if (_db != null)
{
//_db.Close();
_db.Dispose();
_db = null;
}
}
/// <summary>关闭连接,释放对象所占用的系统资源,并清除连接信息。</summary>
public void Dispose() { Close(); }
/// <summary>查询。</summary>
public IQuery Query(string sql) => Query(sql, null);
/// <summary>查询。</summary>
public IQuery Query(string sql, IEnumerable<IDataParameter> parameters)
{
if (string.IsNullOrEmpty(sql)) return Example.InvalidQueryStatement;
const string table = "result";
var connected = Connect();
if (!connected) return Example.InvalidQueryConnection;
var query = new Query();
try
{
var command = new SQLiteCommand();
command.Connection = _db;
command.CommandTimeout = Timeout.Query;
command.CommandText = sql;
if (parameters != null)
{
foreach (var p in parameters)
{
if (p != null) command.Parameters.Add(p);
}
}
using (var dataset = new DataSet())
{
using (var da = new SQLiteDataAdapter(sql, _db))
{
da.Fill(dataset, table);
query.Table = dataset.Tables[table];
}
}
command.Dispose();
query.Success = true;
}
catch (Exception ex)
{
LogError("Query", ex, sql);
query.Success = false;
query.Exception = ex;
}
return query;
}
/// <summary>执行单条 Transact-SQL 语句。</summary>
public IExecute Execute(string sql) => Execute(sql, null);
/// <summary>执行单条 Transact-SQL 语句,并加入参数。</summary>
public IExecute Execute(string sql, IEnumerable<IDataParameter> parameters)
{
if (string.IsNullOrEmpty(sql)) return Example.InvalidExecuteStatement;
var connected = Connect();
if (!connected) return Example.InvalidExecuteConnection;
var transaction = _db.BeginTransaction();
var execute = new Execute();
try
{
var command = new SQLiteCommand();
command.Connection = _db;
command.Transaction = transaction;
command.CommandTimeout = Timeout.Execute;
command.CommandText = sql;
if (parameters != null)
{
foreach (var p in parameters)
{
if (p != null) command.Parameters.Add(p);
}
}
execute.Rows += command.ExecuteNonQuery();
transaction.Commit();
command.Dispose();
execute.Success = true;
}
catch (Exception ex)
{
try { transaction.Rollback(); } catch { }
LogError("Execute", ex, sql);
execute.Success = false;
execute.Exception = ex;
}
try { transaction.Dispose(); } catch { }
return execute;
}
#endregion
#region 属性。
/// <summary>获取当前的 SQLiteConnection 对象。</summary>
public IDbConnection Connection { get => _db; }
/// <summary>获取或设置超时。</summary>
public Timeout Timeout { get => _timeout; set => _timeout = value; }
/// <summary>获取或设置连接字符串,连接字符串非空时将忽略 Path 属性。数据库在线时无法设置。</summary>
public string ConnectionString
{
get
{
if (string.IsNullOrEmpty(_connstring))
{
var temp = new StringBuilder();
temp.Append("data source='", _path, "'; version=3; ");
if (!string.IsNullOrEmpty(_pass)) temp.Append("password=", _pass, "; ");
return temp.ToString();
}
else return _connstring;
}
set
{
if (Online) return;
_connstring = string.IsNullOrEmpty(value) ? "" : value;
}
}
/// <summary>获取或设置数据库路径(文件或内存)。数据库在线时无法设置。</summary>
public string Path
{
get { return _path; }
set
{
if (Online) return;
_path = string.IsNullOrEmpty(value) ? "" : value;
}
}
/// <summary>获取或设置数据库密码。数据库在线时无法设置。</summary>
public string Password
{
get { return _pass; }
set
{
if (Online) return;
_pass = string.IsNullOrEmpty(value) ? "" : value;
}
}
/// <summary>获取或设置数据库密码。数据库在线时无法设置。</summary>
private byte[] PasswordData
{
get { return _passdata; }
set
{
if (Online) return;
_passdata = (value == null) ? BinaryUtility.EmptyBytes : value;
}
}
/// <summary>保存当前数据库到文件,若文件已存在则将重写文件。</summary>
public bool Save(string path)
{
if (!StorageUtility.CreateFile(path, 0, true))
{
LogError("Save", TextUtility.Merge("创建文件 ", path, " 失败。"));
return false;
}
var temp = new Sqlite(path);
var result = Save(temp);
temp.Close();
return result;
}
/// <summary>保存当前数据库到文件,若文件已存在则将重写文件。</summary>
public bool Save(string path, string password)
{
if (!StorageUtility.CreateFile(path, 0, true))
{
LogError("Save", TextUtility.Merge("创建文件 ", path, " 失败。"));
return false;
}
var temp = new Sqlite(path, password);
var result = Save(temp);
temp.Close();
return result;
}
/// <summary>保存当前数据库到目标数据库。</summary>
public bool Save(Sqlite destination)
{
var error = Backup(this, destination);
return string.IsNullOrEmpty(error);
}
/// <summary>加载文件到当前数据库。</summary>
public bool Load(string path)
{
var temp = new Sqlite(path);
var result = Load(temp);
temp.Close();
return result;
}
/// <summary>加载文件到当前数据库。</summary>
public bool Load(string path, params byte[] pass)
{
var temp = new Sqlite(path, pass);
var result = Load(temp);
temp.Close();
return result;
}
/// <summary>加载文件到当前数据库。</summary>
public bool Load(string path, string pass)
{
var temp = new Sqlite(path, pass);
var result = Load(temp);
temp.Close();
return result;
}
/// <summary>加载源数据库到当前数据库。</summary>
public bool Load(Sqlite source)
{
var error = Backup(source, this);
return string.IsNullOrEmpty(error);
}
#endregion
#region ORM。
/// <summary>查询数据库中的所有表名。</summary>
public List<string> TableNames()
{
var list = new List<string>();
if (Connect())
{
var sql = "select name from sqlite_master where type='table' order by name; ";
var query = (Query)Query(sql);
for (int r = 0; r < query.Rows; r++)
{
var cell = query.Text(r, 0);
if (TextUtility.IsBlank(cell)) continue;
list.Add(cell);
}
query.Dispose();
}
return list;
}
/// <summary>查询数据库中的所有视图名。</summary>
public List<string> ViewNames()
{
var list = new List<string>();
if (Connect())
{
var sql = "select name from sqlite_master where type='view' order by name; ";
var query = (Query)Query(sql);
for (int r = 0; r < query.Rows; r++)
{
var cell = query.Text(r, 0);
if (TextUtility.IsBlank(cell)) continue;
list.Add(cell);
}
query.Dispose();
}
return list;
}
/// <summary>查询表中的所有列名。</summary>
public List<string> ColumnNames(string table)
{
var list = new List<string>();
if (Connect())
{
var t = TextUtility.AntiInject(table);
var sql = TextUtility.Merge("pragma table_info('", TextUtility.AntiInject(t), "'); ");
using (var query = Query(sql) as Query)
{
for (int r = 0; r < query.Rows; r++)
{
var cell = query.Text(r, "name");
if (TextUtility.IsBlank(cell)) continue;
list.Add(cell);
}
}
}
return list;
}
/// <summary>创建表,不修改已存在表。成功时返回空字符串,发生异常时返回异常信息。</summary>
public string Initialize(Record model) => model == null ? "参数无效。" : Initialize(model.GetType());
/// <summary>创建表,不修改已存在表。成功时返回空字符串,发生异常时返回异常信息。</summary>
public string Initialize<T>() where T : Record => Initialize(typeof(T));
/// <summary>创建表,不修改已存在表。当现存表中缺少模型中属性对应的列时增加列。成功时返回空字符串,发生异常时返回异常信息。</summary>
public string Initialize(Type model)
{
var structure = null as TableStructure;
try { structure = TableStructure.ParseModel(model); }
catch (Exception exception) { return exception.Message; }
// 连接数据库。
if (!Connect()) return "连接数据库失败。";
// 检查现存表。
var exists = false;
var tables = TableNames();
if (tables.Count > 0)
{
var lower = structure.Table.ToLower();
foreach (var table in tables)
{
if (TextUtility.IsBlank(table)) continue;
if (table.ToLower() == lower)
{
exists = true;
break;
}
}
}
if (exists)
{
return TextUtility.Merge("指定的表已经存在。");
}
else
{
var sqlcolumns = new List<string>();
foreach (var column in structure.Columns.Values)
{
var type = GetColumnDeclaration(column);
if (type == TextUtility.EmptyString) return TextUtility.Merge("类型 ", column.Type.ToString(), " 不受支持。");
sqlcolumns.Add(type);
}
var sql = TextUtility.Merge("create table [", structure.Table, "](", TextUtility.Join(", ", sqlcolumns), "); ");
var execute = Execute(sql);
if (execute.Success) return TextUtility.EmptyString;
return execute.Error;
}
}
/// <summary>插入记录。成功时候返回空字符串,发生异常时返回异常信息。</summary>
public string Insert(Record record)
{
if (record == null) return "参数无效。";
record.FixProperties();
var structure = null as TableStructure;
try { structure = TableStructure.ParseModel(record); }
catch (Exception exception) { return exception.Message; }
var parameters = structure.CreateDataParameters(record, CreateDataParameter);
var sql = GenerateInsertStatement(structure.Table, (IEnumerable<IDataParameter>)parameters);
var execute = Execute(sql, parameters);
if (execute.Success && execute.Rows > 0) return TextUtility.EmptyString;
return execute.Error;
}
/// <summary>更新记录,实体中的 Created 和 Key 属性不被更新。成功时返回空字符串,发生异常时返回异常信息。</summary>
public string Update(Record record)
{
if (record == null) return "参数无效。";
record.FixProperties();
record.Updated = ClockUtility.LucidNow;
var structure = null as TableStructure;
try { structure = TableStructure.ParseModel(record); }
catch (Exception exception) { return exception.Message; }
var parameters = structure.CreateDataParameters(record, CreateDataParameter, "_created", "_key");
var sql = GenerateUpdateStatement(structure.Table, record.Key, parameters);
var execute = Execute(sql, parameters);
if (execute.Success && execute.Rows > 0) return TextUtility.EmptyString;
return execute.Error;
}
/// <summary>获取具有指定 Key 的记录。</summary>
public Result<T> Get<T>(string key) where T : Record => Get<T>(key, 0);
/// <summary>获取具有指定 Key 的记录。</summary>
public Result<T> Get<T>(string key, long flag) where T : Record
{
var k = TextUtility.SafeKey(key);
if (TextUtility.IsBlank(k) == false)
{
try
{
var ts = TableStructure.ParseModel(typeof(T));
var f = (flag == 0) ? TextUtility.EmptyString : TextUtility.Merge(" _flag=", flag.ToString(), " and");
var query = (Query)Query(TextUtility.Merge("select * from [", ts.Table, "] where", f, " _key='", k, "' limit 1; "));
var list = query.Fill<T>();
query.Dispose();
if (list.Count > 0) return new Result<T>(list[0]);
}
catch (Exception ex)
{
return new Result<T>(ex);
}
}
return new Result<T>(new Exception("参数无效。"));
}
/// <summary>查询多条记录。</summary>
public Result<List<T>> Query<T>() where T : Record => Query<T>(0);
/// <summary>查询多条记录。</summary>
public Result<List<T>> Query<T>(long flag) where T : Record
{
try
{
var ts = TableStructure.ParseModel(typeof(T));
var f = (flag == 0) ? TextUtility.EmptyString : TextUtility.Merge(" where _flag=", flag.ToString());
var query = Query(TextUtility.Merge("select * from [", ts.Table, "]", f, "; ")) as Query;
var list = query.Fill<T>();
query.Dispose();
return new Result<List<T>>(list);
}
catch (Exception ex)
{
return new Result<List<T>>(ex);
}
}
/// <summary>获取按指定语句查询到的所有记录。</summary>
public Result<List<T>> Query<T>(string sql) where T : Record
{
using (var query = Query(sql) as Query)
{
if (query.Exception == null) return new Result<List<T>>(query.Fill<T>());
else return new Result<List<T>>(query.Exception);
}
}
/// <summary>查询所有有效的 Key 值。</summary>
public Result<List<string>> Keys<T>() where T : Record => Keys<T>(0);
/// <summary>查询所有有效的 Key 值。</summary>
public Result<List<string>> Keys<T>(long flag) where T : Record => Keys(typeof(T), flag);
/// <summary>查询所有有效的 Key 值。</summary>
public Result<List<string>> Keys(Type model) => Keys(model, 0);
/// <summary>查询所有有效的 Key 值。</summary>
public Result<List<string>> Keys(Type model, long flag)
{
if (model != null)
{
try
{
var list = new List<string>();
var ts = TableStructure.ParseModel((Type)model);
var f = (flag == 0) ? TextUtility.EmptyString : TextUtility.Merge(" where _flag=", flag.ToString());
var query = (Query)Query(TextUtility.Merge("select _key from [", ts.Table, "]", f, "; "));
for (var r = 0; r < query.Rows; r++)
{
var cell = TextUtility.Trim(query.Text(r));
if (cell.Length > 0) list.Add(cell);
}
query.Dispose();
return new Result<List<string>>(list);
}
catch (Exception ex)
{
return new Result<List<string>>(ex);
}
}
return new Result<List<string>>(new Exception("参数无效。"));
}
#endregion
#region static
/// <summary>对文本转义,符合 SQL 安全性。可根据字段类型限制 UTF-8 字节数,默认为 0 时不限制字节数。</summary>
public static string Escape(string text, int bytes = 0)
{
if (text.IsEmpty()) return "";
var t = text ?? "";
t = t.Replace("\\", "\\\\");
t = t.Replace("'", "\\'");
t = t.Replace("\n", "\\n");
t = t.Replace("\r", "\\r");
t = t.Replace("\b", "\\b");
t = t.Replace("\t", "\\t");
t = t.Replace("\f", "\\f");
if (bytes > 5)
{
if (t.GetBytes(Encoding.UTF8).Length > bytes)
{
while (true)
{
t = t.Substring(0, t.Length - 1);
if (t.GetBytes(Encoding.UTF8).Length <= (bytes - 4)) break;
}
t = t + " ...";
}
}
return t;
}
private static string GetColumnTypeName(ColumnType type)
{
switch (type)
{
case ColumnType.Binary:
return "blob";
case ColumnType.Integer:
return "integer";
case ColumnType.Float:
return "float";
case ColumnType.VarChar:
case ColumnType.VarChar255:
case ColumnType.VarCharMax:
return "varchar";
case ColumnType.Text:
return "text";
case ColumnType.NVarChar:
case ColumnType.NVarChar255:
case ColumnType.NVarCharMax:
return "nvarchar";
case ColumnType.NText:
return "ntext";
default:
return null;
}
}
private static string GetColumnDeclaration(ColumnAttribute column)
{
var type = TextUtility.EmptyString;
var length = NumberUtility.RestrictValue(column.Length, 0, 255).ToString();
switch (column.Type)
{
case ColumnType.Binary:
type = "blob";
break;
case ColumnType.Integer:
type = "integer";
break;
case ColumnType.Float:
type = "real";
break;
case ColumnType.VarChar:
case ColumnType.VarChar255:
type = TextUtility.Merge("varchar(", length, ")");
break;
case ColumnType.VarCharMax:
type = TextUtility.Merge("varchar(255)");
break;
case ColumnType.Text:
type = TextUtility.Merge("text");
break;
case ColumnType.NVarChar:
case ColumnType.NVarChar255:
type = TextUtility.Merge("nvarchar(", length, ")");
break;
case ColumnType.NVarCharMax:
type = TextUtility.Merge("nvarchar(255)");
break;
case ColumnType.NText:
type = TextUtility.Merge("ntext");
break;
default:
return TextUtility.EmptyString;
}
return TextUtility.Merge("[", (object)column.Field, "] ", type);
}
/// <summary>创建参数。</summary>
/// <exception cref="ArgumentNullException"></exception>
/// <exception cref="InvalidOperationException"></exception>
public static SQLiteParameter CreateDataParameter(Parameter parameter)
{
if (parameter == null) throw new InvalidOperationException("参数无效。");
return CreateDataParameter(parameter.Name, parameter.Type, parameter.Size, parameter.Value);
}
/// <summary>创建参数。</summary>
public static SQLiteParameter CreateDataParameter(string name, ColumnType type, int size, object value)
{
var n = TextUtility.Trim(name);
if (TextUtility.IsBlank(n)) return null;
var t = GetColumnTypeName(type);
var s = size;
switch (type)
{
case ColumnType.VarChar:
s = NumberUtility.RestrictValue(s, 0, 8000);
break;
case ColumnType.NVarChar:
s = NumberUtility.RestrictValue(s, 0, 4000);
break;
case ColumnType.VarChar255:
case ColumnType.VarCharMax:
case ColumnType.NVarChar255:
case ColumnType.NVarCharMax:
s = NumberUtility.RestrictValue(s, 0, 255);
break;
default:
s = 0;
break;
}
var v = value;
if (v is string && v != null && s > 0)
{
v = TextUtility.RestrictLength((string)v, s);
}
var p = new SQLiteParameter();
p.ParameterName = n;
p.TypeName = t;
p.Value = v;
if (s > 0) p.Size = s;
return p;
}
/// <summary>创建参数。</summary>
public static SQLiteParameter CreateDataParameter(string name, string type, int size, object value)
{
var v = value;
if (value is string && value != null && size > 0)
{
v = TextUtility.RestrictLength((string)value, size);
}
var p = new SQLiteParameter();
p.ParameterName = name;
p.TypeName = type;
p.Value = v;
p.Size = size;
return p;
}
/// <summary>创建参数。</summary>
public static SQLiteParameter CreateDataParameter(string name, string type, object value)
{
var p = new SQLiteParameter();
p.ParameterName = name;
p.TypeName = type;
p.Value = value;
return p;
}
/// <summary>备份数据库,返回错误信息。</summary>
public static string Backup(Sqlite source, Sqlite destination)
{
if (source == null) return "SQLite Backup Failed: Invalid Source";
if (destination == null) return "SQLite Backup Failed: Invalid Destination";
if (!source.Connect()) return "SQLite Backup Failed: Invalid Source Connection";
if (!destination.Connect()) return "SQLite Backup Failed: Invalid Destination Connection";
try
{
source._db.BackupDatabase(destination._db, "main", "main", -1, null, 0);
return "";
}
catch (Exception ex)
{
return "SQLite Load Failed: " + ex.Message;
}
}
/// <summary>创建参数。</summary>
public static IDbDataParameter CreateParameter(string field, DbType type, int size, object value)
{
var p = new SQLiteParameter();
p.ParameterName = field;
p.DbType = type;
p.Size = size;
p.Value = value;
return p;
}
/// <summary>创建参数。</summary>
public static IDbDataParameter CreateParameter(string field, DbType type, object value)
{
var p = new SQLiteParameter();
p.ParameterName = field;
p.DbType = type;
p.Value = value;
return p;
}
/// <summary>整理数据库,压缩未使用的空间。</summary>
public const string Vacuum = "vacuum";
/// <summary>内存数据库的地址。</summary>
public const string Memory = ":memory:";
#endregion
#region ORM
private static string GetParameterName(string parameter)
{
var name = TextUtility.AntiInject(parameter, 255);
if (name.StartsWith("@") && name.Length > 1)
{
name = name.Substring(1, name.Length - 1);
}
return name;
}
private static string GetParameterName(IDataParameter parameter)
{
var name = TextUtility.EmptyString;
if (parameter != null)
{
name = GetParameterName(parameter.ParameterName);
}
return name;
}
private static List<string> GetParametersNames(IEnumerable<IDataParameter> parameters)
{
var columns = new List<string>();
if (parameters != null)
{
foreach (var parameter in parameters)
{
var name = GetParameterName(parameter);
var isblank = TextUtility.IsBlank(name);
if (isblank) continue;
columns.Add(name);
}
}
return columns;
}
private static string GenerateInsertStatement(string table, List<string> columns)
{
var r = TextUtility.EmptyString;
var t = TextUtility.AntiInject(table, 255);
if (columns != null && !TextUtility.IsBlank(t))
{
var count = 0;
var names = new List<string>();
var values = new List<string>();
foreach (var column in columns)
{
//names.Add(TextGenerator.Merge("[", column, "]"));
names.Add(TextUtility.Merge(column));
values.Add("@" + column);
count += 1;
}
var sb = new StringBuilder();
if (count > 0)
{
sb.Append("insert into [", t, "](", TextUtility.Join(", ", names), ") ");
sb.Append("values(", TextUtility.Join(", ", values), "); ");
}
r = sb.ToString();
}
return r;
}
/// <summary>生成 INSERT INTO 语句。表名必须有效,无有效参数时将获取空结果。</summary>
/// <exception cref="System.ArgumentException"></exception>
/// <exception cref="System.ArgumentNullException"></exception>
public static string GenerateInsertStatement(string table, IEnumerable<IDataParameter> parameters)
{
if (table == null) throw new ArgumentNullException(nameof(table));
var t = TextUtility.AntiInject(table, 255);
if (TextUtility.IsBlank(t)) throw new ArgumentException("表名无效。", nameof(table));
var cs = GetParametersNames(parameters);
if (cs.Count < 1) return TextUtility.EmptyString;
return GenerateInsertStatement(t, cs);
}
private static string GenerateUpdateStatement(string table, string key, List<string> columns)
{
var result = TextUtility.EmptyString;
var t = TextUtility.AntiInject(table, 255);
var k = TextUtility.AntiInject(key, 255);
if (columns != null && !TextUtility.IsBlank(t) && !TextUtility.IsBlank(k))
{
var items = new List<string>();
foreach (var column in columns)
{
items.Add(TextUtility.Merge("[", column, "]=@", column));
}
if (items.Count > 0)
{
result = TextUtility.Merge("update [", t, "] set ", TextUtility.Join(", ", items), " where [_key]='", k, "'; ");
}
}
return result;
}
/// <summary>生成 UPDATE 语句,键字段名为“_key”。表名必须有效,键值必须有效,无有效参数时将获取空结果。</summary>
/// <exception cref="System.ArgumentException"></exception>
/// <exception cref="System.ArgumentNullException"></exception>
public static string GenerateUpdateStatement(string table, string key, IEnumerable<IDataParameter> parameters)
{
if (table == null) throw new ArgumentNullException("argTable");
var t = TextUtility.AntiInject(table, 255);
if (TextUtility.IsBlank(t)) throw new ArgumentException("表名无效。", nameof(table));
if (key == null) throw new ArgumentNullException("argKey");
var k = TextUtility.AntiInject(key, 255);
if (TextUtility.IsBlank(k)) throw new ArgumentException("键值无效。", nameof(key));
var columns = GetParametersNames(parameters);
if (columns.Count < 1) return TextUtility.EmptyString;
return GenerateUpdateStatement(t, k, columns);
}
#endregion
}
}
#endif