public static WhereExpression GetPrimaryKeyWhere(Entity entity)
{
var pkFilds = entity.GetPrimaryKeyFields();
var exp = new WhereExpression();
foreach (var field in pkFilds)
{
var newExp = field == entity.GetValue(field.PropertyName);
if (WhereExpression.IsNullOrEmpty(exp))
{
exp = newExp;
}
else
{
exp = WhereExpression.Create(exp, newExp, QueryOperator.And);
}
}
return(exp);
}
/// <summary>
/// 创建删除DbCommand
/// </summary>
/// <param name="tableName"></param>
/// <param name="where"></param>
/// <returns></returns>
public DbCommand CreateDeleteCommand(string tableName, WhereExpression where)
{
if (WhereExpression.IsNullOrEmpty(where))
{
where = WhereExpression.ALL;
}
var translater = CreateTranslater();
StringBuilder sql = new StringBuilder();
sql.Append(ExpressionTranslater.SQL_DELETEFROM);
sql.Append(db.DbProvider.BuildTableName(tableName));
sql.Append(ExpressionTranslater.SQL_WHERE);
sql.Append(translater.TranslateWhere(where));
DbCommand cmd = db.GetSqlStringCommand(sql.ToString());
db.AddCommandParameter(cmd, translater.Params.ToArray());
return(cmd);
}
public static WhereExpression GetPrimaryKeyWhere <T>(object[] pkValues)
where T : Entity
{
var entity = EntityHelper.GetTable <T>();
var pkFilds = entity.GetPrimaryKeyFields();
var exp = new WhereExpression();
for (var i = 0; i < pkFilds.Length; i++)
{
var field = pkFilds[i];
var value = pkValues[i];
if (WhereExpression.IsNullOrEmpty(exp))
{
exp = field == value;
}
else
{
exp = WhereExpression.Create(exp, field == value, QueryOperator.Or);
}
}
return(exp);
}
/// <summary>
/// 创建更新DbCommand
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="fields"></param>
/// <param name="values"></param>
/// <param name="where"></param>
/// <returns></returns>
public DbCommand CreateUpdateCommand <T>(Field[] fields, object[] values, WhereExpression where)
where T : Entity
{
Guard.Check(!EntityHelper.IsReadOnly <T>(), TextResource.CanNotReadOnly.FormatWith(EntityHelper.GetName <T>()));
if (null == fields || fields.Length == 0 || null == values || values.Length == 0)
{
return(null);
}
Guard.Check(fields.Length == values.Length, TextResource.ArgumentShouldEqual.FormatWith("字段的个数", "值的个数"));
int length = fields.Length;
Field identityField = EntityHelper.GetIdentityField <T>();
bool identityExist = !Field.IsNullOrEmpty(identityField);
if (WhereExpression.IsNullOrEmpty(where))
{
where = WhereExpression.ALL;
}
StringBuilder sql = new StringBuilder();
sql.Append(ExpressionTranslater.SQL_UPDDATE);
sql.Append(db.DbProvider.BuildTableName(EntityHelper.GetName <T>()));
sql.Append(ExpressionTranslater.SQL_UPDATE_SET);
List <QueryParameter> list = new List <QueryParameter>();
StringBuilder colums = new StringBuilder();
var appended = false;
for (int i = 0; i < length; i++)
{
if (identityExist && fields[i].PropertyName.Equals(identityField.PropertyName))
{
continue;
}
if (appended)
{
colums.Append(",");
}
appended = true;
colums.Append(fields[i].FieldName);
colums.Append("=");
if (values[i] is Field)
{
Field fieldValue = (Field)values[i];
colums.Append(fieldValue.FieldNameWithTable);
}
else
{
string pname = CreateParmName();
colums.Append(pname);
var p = new QueryParameter(pname, values[i]);
list.Add(p);
}
}
sql.Append(colums);
var translater = CreateTranslater();
sql.Append(ExpressionTranslater.SQL_WHERE);
translater.SetParmStartIndex(paramCounter);
sql.Append(translater.TranslateWhere(where));
list.AddRange(translater.Params);
DbCommand cmd = db.GetSqlStringCommand(sql.ToString());
db.AddCommandParameter(cmd, list.ToArray());
return(cmd);
}
