使用正则表达式：

  -  +警告 -  + [^  - ] +  -  + 

应该这样做。

按照示例，一个简单的方法是搜索'Warnings'行，然后在结果字符串中包含所有剩余部分。

例如

  public   static   string  mytrim（ string  ins）
 {
 string  [] line = ins.Split（ new   char  [] {'  \ n'}）;  //  获取行数 
 int  n; 
 for （n =  0 ; n< line.Length; ++ n）
 {
 if （line [n] .Contains（   - 警告 - ）） //  搜索警告行 
 break ; 
} 
 StringBuilder sb =  new  StringBuilder（）; 
 for （; n <  line.Length; ++ n） //  使用剩余的（可能为空的）部分来构建结果字符串 
 {
 sb。追加（行[N]）; 
 sb.Append（  \ n）; 
} 
 return  sb.ToString（）; 
} 

Hi all

Below is the string i am getting

"One or more warnings have occurred. It is recommended that you follow the
instructions provided to correct the problem then try again.
-----------------------------------Information----------------------------------
Control Station: Check if standby is up
Information HC_CS_27389984778: The standby Control Station is
	 currently powered on. It will be powered off during upgrade, and then
	 later restarted and upgraded.
--------------------------------------------------------------------------------
------------------------------------Warnings------------------------------------
Blades : Check virus checker server configuration
Warning HC_DM_18800115743:
	 * vnxdm01: The virus checker configuration contains only one Virus
	   Checker (VC) server. High availability is compromised. It is
	   recommended to add at least a new VC server.
Action : Use the EMC Celerra AntiVirus MMC to add a new VC server
	 in the virus checker configuration, or edit the configuration
	 file manually.
--------------------------------------------------------------------------------"

i want this

------------------------------------Warnings------------------------------------
Blades : Check virus checker server configuration
Warning HC_DM_18800115743:
	 * vnxdm01: The virus checker configuration contains only one Virus
	   Checker (VC) server. High availability is compromised. It is
	   recommended to add at least a new VC server.
Action : Use the EMC Celerra AntiVirus MMC to add a new VC server
	 in the virus checker configuration, or edit the configuration
	 file manually.
--------------------------------------------------------------------------------"

Please let me know how to do this

Use a regex:

-+Warnings-+[^-]+-+

Should do it.

Following the example, a simple approach would be searching for the 'Warnings' line and then include in your result string all the remaining part.
e.g.

public static string mytrim(string ins)
{
  string[] line = ins.Split(new char[] { '\n' }); // obtain an array of lines
  int n;
  for (n=0; n<line.Length; ++n)
  {
     if (line[n].Contains("-Warnings-")) // search for the 'Warnings' line
       break;
  }
  StringBuilder sb = new StringBuilder();
  for (; n < line.Length; ++n) // use the remaining (possibly empty) part for building the result string
  {
     sb.Append(line[n]);
     sb.Append("\n");
  }
  return sb.ToString();
}