JAVA - String 中删除指定字符（11种方法）

╰+攻爆jí腚メ 2022-01-29 14:23 599阅读 0赞

这边给大家介绍一下，String中是如何删除指定字符，博主粗略总结了11种方法，如果有不足或者遗漏希望读者能够不吝赐教。

![640_wx_fmt_jpeg_tp_webp_wxfrom_5_wx_lazy_1_wx_co_1][]

作者：CoderPLDQ

[https://blog.csdn.net/li767517488/article/details/64919194][https_blog.csdn.net_li767517488_article_details_64919194]

**第一种方法**

通过循环从前往后遍历，如果不是要删除的字符则加到处理后的字符串中，代码如下：

public String deleteCharString0(String sourceString, char chElemData) {
            String deleteString = "";
            for (int i = 0; i < sourceString.length(); i++) {
                if (sourceString.charAt(i) != chElemData) {
                    deleteString += sourceString.charAt(i);
                }
            }
            return deleteString;
        }

**第二种方法**

通过循环确定要删除字符的位置索引，然后通过分割字符串的形式，将子字符串拼接，注意最后一段子字符串和源字符串中没有要删除字符的情况，代码如下：

public String deleteCharString1(String sourceString, char chElemData) {
            String deleteString = "";
            int iIndex = 0;
            for (int i = 0; i < sourceString.length(); i++) {
                if (sourceString.charAt(i) == chElemData) {
                    if (i > 0) {
                        deleteString += sourceString.substring(iIndex, i);
                    }
                    iIndex = i + 1;
                }
            }
            if (iIndex <= sourceString.length()) {
                deleteString += sourceString.substring(iIndex, sourceString.length());
            }
            return deleteString;
        }

**第三种方法**

原理同上，只不过查找要删除字符位置采用String类中的函数执行，效率不如上面的高，代码如下：

public String deleteCharString2(String sourceString, char chElemData) {
            String deleteString = "";
            int iIndex = 0;
            int tmpCount = 0;
            do {
                tmpCount = sourceString.indexOf(chElemData, iIndex);
                if (tmpCount > 0) {
                    deleteString += sourceString.substring(iIndex, tmpCount);
                }
                if (tmpCount != -1) {
                    iIndex = tmpCount + 1;
                }
            } while (tmpCount != -1);
            if (iIndex <= sourceString.length()) {
                deleteString += sourceString.substring(iIndex, sourceString.length());
            }
            return deleteString;
        }

**第四种方法**

原理与上方基本一致，只不过这次采用倒序方式，这里的坑就更多了，一定要注意索引的取值范围和是否合法，代码如下：

public String deleteCharString3(String sourceString, char chElemData) {
            String deleteString = "";
            int iIndex = sourceString.length();
            int tmpCount = 0;
            do {
                tmpCount = sourceString.lastIndexOf(chElemData, iIndex - 1);
                if (tmpCount < sourceString.length() && tmpCount >= 0) {
                    deleteString = sourceString.substring(tmpCount + 1, iIndex) + deleteString;
                }
                if (tmpCount != -1) {
                    iIndex = tmpCount;
                }
            } while (tmpCount != -1);
            if (iIndex >= 0) {
                deleteString = sourceString.substring(0, iIndex) + deleteString;
            }
    
            return deleteString;
        }

**第五种方法**

通过采用正则的方式和replaceAll函数，本种方法要注意特殊字符，例如正则中的 “.”字符，需要对特殊字符进行转义，代码如下：

public String deleteCharString4(String sourceString, char chElemData) {
            String deleteString = "";
            final String strTable = "|^$*+?.(){}\\";
            String tmpRegex = "["; 
            for (int i = 0; i < strTable.length(); i++) {
                if (strTable.charAt(i) == chElemData) {
                    tmpRegex += "\\";
                    break;
                }
            }
            tmpRegex += chElemData + "]";
            deleteString = sourceString.replaceAll(tmpRegex, "");
            return deleteString;
        }

**第六种方法**

采用正则的方式将字符串分割成几个子字符串，再将子字符串进行拼接，代码如下：

public String deleteCharString5(String sourceString, char chElemData) {
            String deleteString = "";
            final String strTable = "|^$*+?.(){}\\";
            String tmpRegex = "["; 
            for (int i = 0; i < strTable.length(); i++) {
                if (strTable.charAt(i) == chElemData) {
                    tmpRegex += "\\";
                    break;
                }
            }
            tmpRegex += chElemData + "]";
            String[] tmpStringArray = sourceString.split(tmpRegex);
            for (int i = 0; i < tmpStringArray.length; i++) {
                deleteString += tmpStringArray[i];
            }
            return deleteString;
        }

**第七种方法**

将字符编程可读序列，在通过 String 类中的方法替换，代码如下：

public String deleteCharString6(String sourceString, char chElemData) {
            String tmpString = "";
            tmpString += chElemData;
            tmpString.subSequence(0, 0);
            String deleteString = "";
            deleteString = sourceString.replace(tmpString, deleteString.subSequence(0, 0));
            return deleteString;
        }

**第八种方法**

把原字符串转化为字符数组，然后原理与直接插入排序原理类似，代码如下：

public String deleteCharString7(String sourceString, char chElemData) {
            String deleteString = "";
            char[] Bytes = sourceString.toCharArray();
            int iSize = Bytes.length;
            for (int i = Bytes.length - 1; i >= 0; i--) {
                if (Bytes[i] == chElemData) {
                    for (int j = i; j < iSize - 1; j++) {
                        Bytes[j] = Bytes[j + 1];
                    }
                    iSize--;
                }
            }
            for (int i = 0; i < iSize; i++) {
                deleteString += Bytes[i];
            }
            return deleteString;
        }

**第九种方法**

原理与 第一种方法 类似，本次采用 stringBuffer 类中的 append 方法进行操作，我认为效率应该高于第一种。

public String deleteCharString8(String sourceString, char chElemData) {
            StringBuffer stringBuffer = new StringBuffer("");
            for (int i = 0; i < sourceString.length(); i++) {
                if (sourceString.charAt(i) != chElemData) {
                    stringBuffer.append(sourceString.charAt(i));
                }
            }
            return stringBuffer.toString();
        }

**第十种方法**

采用 stringBuffer 类中的 replace and indexOf 方法（\_ 故意凑方法），代码如下：

public String deleteCharString9(String sourceString, char chElemData) {
            String tmpString = "";
            tmpString += chElemData;
            StringBuffer stringBuffer = new StringBuffer(sourceString);
            int iFlag = -1;
            do {
                iFlag = stringBuffer.indexOf(tmpString);
                if (iFlag != -1) {
                    stringBuffer = stringBuffer.replace(iFlag, iFlag + 1, "");
                }
            } while (iFlag != -1);
            return stringBuffer.toString();
        }

**第十一种方法**

采用 stringBuffer 类中的 deleteCharAt 和 indexOf 直接删除

public String deleteCharString10(String sourceString, char chElemData) {
            String tmpString = "";
            tmpString += chElemData;
            StringBuffer stringBuffer = new StringBuffer(sourceString);
            int iFlag = -1;
            do {
                iFlag = stringBuffer.indexOf(tmpString);
                if (iFlag != -1) {
                    stringBuffer.deleteCharAt(iFlag);
                }
            } while (iFlag != -1);
            return stringBuffer.toString();
        }

**程序运行截图：**

![image][]

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[https_blog.csdn.net_li767517488_article_details_64919194]: https://blog.csdn.net/li767517488/article/details/64919194
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