学步园

//字符是否为汉字<br /> public bool IsChinese(char c)<br /> {<br /> return (int)c >= 0x4E00 && (int)c <= 0x9FA5;<br /> }<br /> //获得字节长度<br /> private int getLengthb(string str)<br /> {<br /> return System.Text.Encoding.Default.GetByteCount(str);<br /> }</p> <p> //c#的中英文混合字符串截取指定长度,startidx从0开始 by gisoracle@126.com<br /> public string getStrLenB(string str, int startidx, int len)<br /> {<br /> int Lengthb = getLengthb(str);<br /> if (startidx + 1 > Lengthb)<br /> {<br /> return "";<br /> }<br /> int j = 0;<br /> int l = 0;<br /> int strw = 0;//字符的宽度<br /> bool b = false;<br /> string rstr = "";<br /> for (int i = 0; i < str.Length; i++)<br /> {<br /> char c = str[i];<br /> if (j >= startidx)<br /> {<br /> rstr = rstr + c;<br /> b = true;<br /> }<br /> if (IsChinese(c))<br /> {<br /> strw = 2;<br /> }<br /> else<br /> {<br /> strw = 1;<br /> }<br /> j = j + strw;<br /> if (b)<br /> {<br /> l = l + strw;<br /> if ((l+1)>= len) break;</p> <p> }</p> <p> }<br /> return rstr;</p> <p> }</p> <p> private void button4_Click(object sender, EventArgs e) //测试by yl gisoracle@126.com<br /> {<br /> MessageBox.Show(getStrLenB("gisoracle欢迎你gisoracle", 0, 10));//gisoracle<br /> MessageBox.Show(getStrLenB("gisoracle欢迎你gisoracle", 1, 10));//isoracle欢<br /> MessageBox.Show(getStrLenB("gisoracle欢迎你gisoracle", 2, 10));//isoracle欢<br /> }</p> <p>