C# Datatable筛选过滤的四种方法实现

// 单条件筛选
DataRow[] rows = dt.Select("Age > 25");

// 多条件组合
DataRow[] rows = dt.Select("Name LIKE '张%' AND Age > 20");

// 带排序的筛选
DataRow[] rows = dt.Select("Dept='销售部'", "HireDate DESC");

// 无排序参数时行为
DataRow[] rows1 = dt.Select("Age > 25"); // 顺序取决于是否有主键

// 显式指定排序
DataRow[] rows2 = dt.Select("Dept='销售部'", "HireDate DESC"); // 强制按指定字段排序

// 我常使用
var query = dt.AsEnumerable()
              .Where(row => row["Age"]?.toString() =="25");

// 基础查询
var query = dt.AsEnumerable()
              .Where(row => row.Field<int>("Age") > 25);

// 多条件+投影
var results = from row in dt.AsEnumerable()
              where row.Field<string>("Name").Contains("张")
              select new {
                  ID = row["ID"],
                  Name = row["Name"]
              };

// 保持原始顺序
var query1 = dt.AsEnumerable().Where(row => row.Field<int>("Age") > 25);

// 显式排序
var query2 = from row in dt.AsEnumerable()
             orderby row.Field<DateTime>("CreateDate") descending
             select row;

DataView dv = new DataView(dt);
dv.RowFilter = "Status='Active'";
dv.Sort = "CreateTime DESC";

// 绑定到控件
dataGridView1.DataSource = dv;

DataView dv = new DataView(dt);
dv.RowFilter = "Status='Active'"; // 不影响顺序
dv.Sort = "Salary DESC"; // 显式设置排序

string dynamicFilter = $"Age > {minAge}";
if (!string.IsNullOrEmpty(nameFilter)) 
    dynamicFilter += $" AND Name LIKE '%{nameFilter.Replace("'","''")}%'";

DataRow[] rows = dt.Select(dynamicFilter);

string condition = "Age > 30";
if(includeDepartment) 
    condition += " AND Dept='IT'";

// 排序取决于Select方法的第二个参数
DataRow[] rows = dt.Select(condition, "Name ASC"); 

// 列名包含特殊字符
dt.Select("[#Rank] > 5"); 

// 值包含单引号
dt.Select($"Name='{input.Replace("'","''")}'");:ml-citation{ref="25,42" data="citationList"}