修改ESL EDI增加运费协议号必填提示

Myshipping.Application/EDI/ESLEdiHelper.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Diagnostics.Contracts;
 using System.IO;
 using System.Runtime.InteropServices;
 using System.Text;
@@ -366,6 +367,9 @@ namespace Myshipping.Application.EDI.ESL
                 if (string.IsNullOrEmpty(headData.ESLLINECODE))
                 { error = error + "<br />提单号：" + headData.MBLNO + " 航司航线不能为空"; }
 
+                if (string.IsNullOrWhiteSpace(headData.CONTRACTNO))
+                { error = error + "<br />提单号：" + headData.MBLNO + " 运费协议号不能为空"; }
+                
                 if (string.IsNullOrEmpty(headData.KINDPKGS_EDI_CODE))
                 { error = error + "<br />提单号：" + headData.MBLNO + " 包装EDI代码不能为空"; }
                 if (headData.PKGS == 0)