假如一个表中一字段的数据类型为Text,比如插入此字段中的记录有大于100字节,有小与100字节的,如何提取指定长度为100字节?如下代码如何表示?
<% OleDbConnection conn = new OleDbConnection(ConfigurationManager.AppSettings["conStr"]);
OleDbCommand cmd = new OleDbCommand("select top 11 * from HotTopic order by ID ",conn);
conn.Open();
OleDbDataReader dr;
dr = cmd.ExecuteReader();
while (dr.Read())
{
string str=dr["HotTitle"].ToString();
Response.Write("·<a href='http://"+dr["HotImage"].ToString()+"'>"+str+"</a> <br>");
}
%>
<% OleDbConnection conn = new OleDbConnection(ConfigurationManager.AppSettings["conStr"]);
OleDbCommand cmd = new OleDbCommand("select top 11 * from HotTopic order by ID ",conn);
conn.Open();
OleDbDataReader dr;
dr = cmd.ExecuteReader();
while (dr.Read())
{
string str=dr["HotTitle"].ToString();
Response.Write("·<a href='http://"+dr["HotImage"].ToString()+"'>"+str+"</a> <br>");
}
%>
string str = dr["HotTitle"].ToString() + string.Format("{0," + 100 + "}", ""); // 先加100个空格
str = str.Substring(0, 100); // 取到第100个字符的位置注意这里的长度是字符不是字节
如有有汉字在str中得占2个字节,需用Encoding.Default.GetBytes()/GetString()处理