微信小程序背景图-微信小程序将网络图片设置到background-image上能显示的

微信小程序 将网络图片设置到background-image上能显示微信小程序背景图，相关代码如下：

微信小程序 将本地拍照/相机选择的图片设置到background-image上是不能显示的。

解决办法1：使用wx.getFileSystemManager将本地拍照/相机选择的图片转成base64格式,设置到background-image上。

wx.chooseImage({
    count: 1, // 默认9
    sizeType: ['original', 'compressed'], //  可以指定是原图还是压缩图，默认二者都有
    sourceType: ['album', 'camera'], //  可以指定来源是相册还是相机，默认二者都有
    success: function(e) { // 选择图片成功
      console.log("本次选择图片" + JSON.stringify(e.tempFilePaths));
      var baseImg = "";
      wx.getFileSystemManager().readFile({
        filePath: e.tempFilePaths[0], // 选择图片返回的相对路径
        encoding: 'base64', // 编码格式
        success: res => { // 转码成功的回调
          baseImg = 'data:image/png;base64,' + res.data;
          console.log('data:image/png;base64,' + res.data);
          // 后续的逻辑处理
          ...
          ...
        }
      })
    },
    fail: function(error) {
      console.error("调用本地相册文件时出错")
      console.warn(error)
    },
    complete: function() {
    }
  })

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解决办法2：弃用background-image赋值的方式微信小程序背景图，改用image组件的src属性,本地拍照/相机选择的图片都能显示。