C#如何判斷一個字串中中文和字母或數位個數

int inum=0;

int ichar = 0;

int ichi = 0;

string strTemp;

for (int i = 0; i < this.textBox1.Text.Length; i++)

{
     strTemp=this.textBox1.Text.Substring(i,1);

     if ("0123456789０１２３４５６７８９".IndexOf(strTemp) > -1)

     {

          inum++;

     }

     else if ("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZＡＢＣＤＥＦＧＨＩＪＫＬＭＮＯＰＱＲＳＴＵＶＷＸＹＺ".IndexOf(strTemp) > -1)

     {

          ichar++;

     }

     else

     {

          ichi++;

     }

}

this.textBox2.Text = "數字：" + inum.ToString();

this.textBox3.Text = "字母：" + ichar.ToString();

this.textBox4.Text = "漢字：" + ichi.ToString();