/// <summary>
/// 创建不等于条件表达式
/// </summary>
/// <param name="fieldname">左边字段名称</param>
/// <param name="parametname">右边参数名称</param>
/// <param name="parametvalue">右边参数值</param>
/// <param name="paramet">返回与条件表达式一起使用的参数表达式</param>
/// <returns></returns>
internal static string CreateNotEqWhere(
string fieldname,
string parametname,
object parametvalue,
out IDataParamet paramet)
{
paramet = null;
if (string.IsNullOrEmpty(fieldname) || string.IsNullOrEmpty(parametname))
{
return(null);
}
string left = fieldname;
if (MsSqlServerHelper.IsValidFieldName(fieldname))
{
left = MsSqlServerHelper.GetFeildNameInSqlExpress(fieldname);
}
if (parametvalue == null)
{
return(string.Format("{0} IS NOT NULL", left));
}
string right = MsSqlServerHelper.GetParametName(parametname);
paramet = new DataParamet()
{
Direction = System.Data.ParameterDirection.Input, Name = parametname, Value = parametvalue, ValueType = parametvalue.GetType()
};
return(string.Format("{0}<>{1}", left, right));
}
/// <summary>
/// 创建以parametvalue开始或在parametvalue中以列的值开始的条件表达式
/// </summary>
/// <param name="fieldname">列字段名称</param>
/// <param name="parametname">参数名称</param>
/// <param name="parametvalue">参数值</param>
/// <param name="parametIsExpress">是否是取在parametvalue中以列的值开始的条件表达式</param>
/// <param name="paramet"></param>
/// <returns></returns>
internal static string CreateFirstIndexOfWhere(
string fieldname,
string parametname,
string parametvalue,
bool parametIsExpress,
out IDataParamet paramet)
{
paramet = null;
if (string.IsNullOrEmpty(fieldname) || string.IsNullOrEmpty(parametname))
{
return(null);
}
string left = fieldname;
if (MsSqlServerHelper.IsValidFieldName(fieldname))
{
left = MsSqlServerHelper.GetFeildNameInSqlExpress(fieldname);
}
if (parametvalue == null)
{
return(null);
}
string right = MsSqlServerHelper.GetParametName(parametname);
paramet = new DataParamet()
{
Direction = System.Data.ParameterDirection.Input, Name = parametname, Value = parametvalue, ValueType = parametvalue.GetType()
};
if (parametIsExpress)
{
return(string.Format("CHARINDEX({1},{0})=1", left, right));
}
else
{
return(string.Format("CHARINDEX({0},{1})=1", left, right));
}
}