如何在base64对象中获取base64字符串

Question

我想在"data:application/vnd.openxmlformats-officedocument.wordprocessingml.dococument；base64，"之后获取它。我想提取以"UEsDBBQACAgIANBmkE8AAAAA…"开头的数据。我该怎么做？

Base64输出

ADDENDUMA: "data:application/vnd.openxmlformats-officedocument.wordprocessingml.document;base64,UEsDBBQACAgIANBmkE8AAAAAAAAAAAAAAAALAAAAX3JlbHMvLnJlbHOt0sFKAzEQBuB7n2KZe3e2VURks72I0JtIfYCQzO4Gm0xIplrf3lAKulBWwR4z+efnI6TdHP2+eqeUHQcFq7qBioJh68Kg4HX3tLyHTbdoX2ivpUTy6GKuyk7ICkaR+ICYzUhe55ojhXLTc/JayjENGLV50wPhumnuMP3sgG7SWW2tgrS1K6h2n5H+

React JS

if(convertedResult){
props.values.addendumA = convertedResult
props.values.addendumA = JSON.stringify(props.values.addendumA)
console.log('ADDENDUMA: '+props.values.addendumA)
changeSelectedA(props.values.addendumA)
}

Answer 1

您可以使用一个简单的Regex表达式

const regex = '(.*)(base64,)(.*)';
var macthes = props.values.addendumA.match(regex);
var val = macthes[3]; //This is what you're looking for

Answer 2

您可以使用base64,进行拆分，移除第一个元素，然后再次连接。

let parts = addendumA.split("base64,")
parts.shift()
parts.join("")