.net – 如何处理System.Data.DataTableExtensions.CopyToDataTable()中的缺陷

Imports System.Data.DaTarowExtensions
    Imports System.Data.DataTableExtensions

    Public Class SomeClass
            Private Shared Function GetData() As DataTable
                Dim Data As DataTable

                Data = LegacyADO.NETDBCall


                Data = Data.AsEnumerable.Where(Function(dr) dr.Field(Of Integer)("SomeField") = 5).copyToDataTable()


                Return Data

            End Function
    End Class

someDataTable.AsEnumerable().Where(r => r.Field<string>("SomeField") == "SomeValue").AsDataView().ToTable();

.net 手动建DataTable 获取DataTable列名 修改DataTable 列的顺序

//创建 表
DataTable tables = new DataTable();
//添加 创建 列
//第一列
DataColumn cums = new DataColumn();
cums.ColumnName = "UserName";
cums.DataType = typeof(string);
tables.Columns.Add(cums);
cums = new DataColumn();
cums.ColumnName = "Age";
cums.DataType = typeof(string);
tables.Columns.Add(cums);
tables.Columns.Add("Address", typeof(string));  这种用的较多
tables.Columns["Address"].SetOrdinal(0);  //修改DataTable 列的顺序
string[] columnNames = GetColumnsByDataTable(tables);
string ss = columnNames[0];   

        /// <summary>
        /// 根据datatable获得列名
        /// </summary>
        /// <param name="dt">表对象</param>
        /// <returns>返回结果的数据列数组</returns>   
       public  string[] GetColumnsByDataTable(DataTable dt)
        {
            string[] strColumns = null;
            if (dt.Columns.Count > 0)
            {
                int columnNum = 0;
                columnNum = dt.Columns.Count;
                strColumns = new string[columnNum];
                for (int i = 0; i < dt.Columns.Count; i++)
                {
                    strColumns[i] = dt.Columns[i].ColumnName;
                }
            }
            return strColumns;
        }

.net将一个DataTable拆分成n个DataTable

/// <summary> 
        /// 分解数据表 
        /// </summary> 
        /// <param name="originalTab">需要分解的表</param> 
        /// <param name="rowsNum">每个表包含的数据量</param> 
        /// <returns></returns> 
        public DataSet SplitDataTable(DataTable originalTab, int rowsNum)
       {             
           //获取所需创建的表数量 
            int tableNum = originalTab.Rows.Count / rowsNum; 
 
            //获取数据余数 
            int remainder = originalTab.Rows.Count % rowsNum; 
             
            DataSet ds = new DataSet(); 
 
            //如果只需要创建1个表，直接将原始表存入DataSet 
            if (tableNum == 0) 
            { 
                ds.Tables.Add(originalTab); 
            } 
            else 
            {
                //如果不能整除则需要+1
                if (remainder!=0)
                {
                    tableNum += 1;
                }
                DataTable[] tableSlice = new DataTable[tableNum]; 
             
                //Save orginal columns into new table.             
                for (int c = 0; c<tableNum; c++) 
                { 
                    tableSlice[c] = new DataTable(); 
                    foreach(DataColumn dc in originalTab.Columns) 
                    {                     
                        tableSlice[c].Columns.Add(dc.ColumnName,dc.DataType);                     
                    } 
                }                                                             
                //Import Rows 
                for (int i = 0; i<tableNum; i ++) 
                { 
                    // if the current table is not the last one 
                    if (i != tableNum -1) 
                    { 
                        for(int j = i * rowsNum; j< ((i+1)* rowsNum); j++) 
                        { 
                            tableSlice[i].ImportRow(originalTab.Rows[j]); 
                        } 
                    } 
                    else 
                    { 
                        for(int k = i * rowsNum; k< ((i+1)* rowsNum+remainder); k++) 
                        { 
                            tableSlice[i].ImportRow(originalTab.Rows[k]); 
                        } 
                    } 
                }             
             
                //add all tables into a dataset                 
                foreach(DataTable dt in tableSlice) 
                { 
                    ds.Tables.Add(dt); 
                } 
            } 
            return ds; 
        } 

Angular - 如何在@tusharghoshbd ngx-datatable 中将 id 自定义为自动增量

export class SiteInfoComponent implements OnInit {
  @ViewChild(''actionTpl'',{
    static: true
  })
  actionTpl: TemplateRef < any > ;
  @ViewChild(''addresstpl'',{
    static: true
  })
  addresstpl: TemplateRef < any > ;
  @ViewChild(''activeTpl'',{
    static: true
  })
  activeTpl: TemplateRef < any > ;
  @ViewChild(''departmentTpl'',{
    static: true
  })

  isLoading: boolean = false;
  options: any = {};
  userInfoList: any[] = [];
  columns: any = {};

  constructor(private userInfoService: UserInfoService) {}

  ngOnInit(): void {
    this.options = {
      loader: true
    };
    this.columns = [{
        key: ''id'',title: ''<div> ID</div>'',width: 60,sorting: true,align: {
          head: ''center'',body: ''center''
        },vAlign: {
          head: ''bottom'',body: ''middle''
        }
      },{
        key: ''first_name'',title: ''<div>First Name</div>'',width: 100
      },{
        key: ''last_name'',title: ''<div>Last Name</div>'',{
        key: ''department'',title: ''<div>Department</div>'',align: {
          head: ''left''
        },width: 100,cellTemplate: this.departmentTpl
      },{
        key: '''',title: ''<div>Action</div>'',sorting: false,width: 80,cellTemplate: this.actionTpl
      }
    ];

    this.isLoading = true;
    this.userInfoService.getAllUserDetail().subscribe(
      data => {
        console.log(data);
        this.userInfoList = [data.results.user];

        this.options = {
          ...this.options,loader: false
        };
      },error => {
        this.isLoading = false;
      }
    );
  }
}