c# 字符串截取问题

发布网友发布时间：2023-07-05 03:14

我来回答

共2个回答

热心网友时间：2024-12-01 19:43

复制黏贴就可以用了看看图片是不是你想要的效果

后台代码

using System;

using System.Data;

using System.Configuration;

using System.Collections;

using System.Web;

using System.Web.Security;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Web.UI.WebControls.WebParts;

using System.Web.UI.HtmlControls;

using System.Text.RegularExpressions;

public partial class test_Default4 : System.Web.UI.Page

{

protected void Page_Load(object sender, EventArgs e)

{ }

public int[] FindPositions(string strSource, string strKey)

{

//这里由hlxwell提供

MatchCollection mc = Regex.Matches(strSource, strKey);

string a = "";

foreach (Match m in mc)

{

//把所有位置用,隔开

a += m.Index + ",";

}

//根据,把位置的值分开来

string[] s = a.Split(',');

int[] sPosition = new int[s.Length - 1];

for (int i = 0; i < s.Length - 1; i++)

{

sPosition[i] = Convert.ToInt32(s[i]);

}

return sPosition;

}

protected void Button1_Click(object sender, EventArgs e)

{

string str = "";

string tou;

string end;

str = this.ctext.Text;

tou = this.chead.Text.Trim();

end = this.cend.Text.Trim();

try {

int[] number = FindPositions(str, tou);

int len = number[0]+tou.Length;

string subs = str.Substring(len, str.Length - len);

int[] number2 = FindPositions(subs, end);

string subs2 = subs.Substring(0, number2[0]);

Response.Write(subs2); }

catch (Exception ex)

{

Response.Write("截取失败！");

}

前台<body>：

<body>

<div>

要截取的内容<br />

<asp:TextBox ID="ctext" runat="server" TextMode="MultiLine" Height="125px" Width="330px"></asp:TextBox><br />

<br />

开头

<asp:TextBox ID="chead" runat="server" Width="89px"></asp:TextBox>结尾

<asp:TextBox ID="cend" runat="server" Width="82px"></asp:TextBox>

<asp:Button ID="Button1" runat="server" Text="Button" OnClick="Button1_Click" /></div>

</form>

</body>

热心网友时间：2024-12-01 19:43

有很多方法，如果都是from/to/subject这种形式的，逐行读取并判断是否是某某开头就可以的，当然，也可以用正则表达式查找符合要求的。