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å串fromindexä½ååºç°ç第ä¸ä¸ªä½ç½®.没ææ¾å°è¿å -1
egï¼String str="a2dfcfar1bzvb";
System.out.println(str.indexOf(97,2));
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açASCII为97ï¼å°±ä»då¼å§æ¾aæ¾å°äºè¾åºaæå¨
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String.indexOfå½æ°ç¨æ³å°ç»
1. indexOfçåæ°æ¯String, startIndex: Number;
indexOfç
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2. Function indexOf å
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1). Strng.indexOf(substring) //æç´¢Stringä¸çsubstring,é»è®¤ä»0ä½å¼å§ï¼
2). String.indexOf(substring, int m) //æç´¢Stringä¸çsubstring, é»è®¤ä»ç¬¬mä½å¼å§ï¼
public class Hehe
{
int i;
int x;
String ip= null;
String input1 = null;
String input2 = null;
public void main(String args[]){
ip = "126.168.1.1";
i = ip.indexOf('.');
x = ip.indexOf('.',i+1);
input1 = ip.substring(0,i);
input2 = ip.substring(i+1, x);
System.out.println("the input1 is "+input1);
System.out.println("the input2 is "+input2);
}
}
ç»ææ¯
the input1 is 126
the input2 is 168